Subject: Re: [Shop-talk] Furnace Filters

From: Ian McFetridge <[email-masked]>
Date: Mon, 13 Dec 2021 17:26:51 -0500

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Hi Jim,
That is basically what I did with our HVAC system when I couldn't get the
4" filters during CV supply craziness.  The 4" was supposed to be changed
between 4 and 6 months, so I just bought the 1" filter and changed it each
month.  I did use bent wire (like what is used to hold an insulation batt
between joists) to press the 1" filter against the side of the enclosure.
We've since moved, but I did not have any issues with it; in fact, I think
changing the 1" filter more often did a better job balancing filtration and
flow.

Best,
Ian

On Mon, Dec 13, 2021 at 5:20 PM Jim Stone <[email-masked]> wrote:

> The company that installed my HVAC system a few years ago used a filter
> box on the return line that takes 20=E2=80=9D x 25" x* 4=E2=80=9D* filter=
s, which is an
> unusual, and thus expensive, size - filters generally run about $25 each =
-
> that is not readily available other than online.  During construction, my
> general contractor just had a cheap 20=E2=80=9D x 25" x *1=E2=80=9D *filt=
er in there that
> seemed to work just fine.  I checked the installation instructions for th=
e
> furnace and there are no specifications for the filters, other than that
> they need to be changed regularly, which is getting pretty expensive.  Is
> there any reason I couldn=E2=80=99t just use 1=E2=80=9D filters, which ar=
e less than half
> the price?  Maybe even put two of them in the box, a good one first to
> catch most of the dust and a cheap one like the contractor used as a
> secondary one.  It is a snug fit and I don=E2=80=99t think there is any d=
anger of
> them tipping, but two would make it impossible.
>
> Thanks,
> Jim
> _______________________________________________
>
> [email-masked]
> Donate: http://www.team.net/donate.html
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> Archive: http://www.team.net/pipermail/shop-talk
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> http://autox.team.net/mailman/options/shop-talk/[email-masked]
>
>

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<div dir=3D"ltr">Hi Jim,=C2=A0<div>That is basically what I did with our HV=
AC system when I couldn&#39;t get the 4&quot; filters during CV supply craz=
iness.=C2=A0 The 4&quot; was supposed to be changed between 4 and 6 months,=
 so I just bought the 1&quot; filter and changed it each month.=C2=A0 I did=
 use bent wire (like what is used to hold an insulation batt between joists=
) to press the 1&quot; filter against the side of the enclosure.=C2=A0 We&#=
39;ve since moved, but I did not have any issues with it; in fact, I think =
changing the 1&quot; filter more often did a better job balancing filtratio=
n and flow.=C2=A0=C2=A0</div><div><br></div><div>Best,<br>Ian</div></div><b=
r><div class=3D"gmail_quote"><div dir=3D"ltr" class=3D"gmail_attr">On Mon, =
Dec 13, 2021 at 5:20 PM Jim Stone &lt;<a href=3D"mailto:[email-masked]=
m">[email-masked]</a>&gt; wrote:<br></div><blockquote class=3D"gmail_=
quote" style=3D"margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,=
204);padding-left:1ex"><div style=3D"overflow-wrap: break-word;">The compan=
y that installed my HVAC system a few years ago used a filter box on the re=
turn line that takes 20=E2=80=9D x 25&quot; x<b> 4=E2=80=9D</b> filters, wh=
ich is an unusual, and thus expensive, size - filters generally run about $=
25 each - that is not readily available other than online.=C2=A0 During con=
struction, my general contractor just had a=C2=A0cheap 20=E2=80=9D x 25&quo=
t; x <b>1=E2=80=9D </b>filter in there that seemed to work just fine.=C2=A0=
 I checked the installation instructions for the furnace and there are no s=
pecifications for the filters, other than that they need to be changed regu=
larly, which is getting pretty expensive.=C2=A0 Is there any reason I could=
n=E2=80=99t just use 1=E2=80=9D filters, which are less than half the price=
?=C2=A0 Maybe even put two of them in the box, a good one first to catch mo=
st of the dust and a cheap one like the contractor used as a secondary one.=
=C2=A0 It is a snug fit and I don=E2=80=99t think there is any danger of th=
em tipping, but two would make it impossible.<div><br></div><div>Thanks,</d=
iv><div>Jim</div></div>_______________________________________________<br>
<br>
<a href=3D"mailto:[email-masked]" target=3D"_blank">Shop-talk@aut=
ox.team.net</a><br>
et=3D"_blank">http://www.team.net/donate.html</a><br>
Archive: <a href=3D"http://www.team.net/pipermail/shop-talk" rel=3D"norefer=
rer" target=3D"_blank">http://www.team.net/pipermail/shop-talk</a> <a href=
=3D"http://autox.team.net/archive" rel=3D"noreferrer" target=3D"_blank">htt=
p://autox.team.net/archive</a><br>
<br>
alk/[email-masked]" rel=3D"noreferrer" target=3D"_blank">http://=
autox.team.net/mailman/options/shop-talk/[email-masked]</a><br>
<br>
</blockquote></div>

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_______________________________________________

[email-masked]
Archive: http://www.team.net/pipermail/shop-talk http://autox.team.net/archive

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From: David Scheidt <[email-masked]>
Date: Mon, 13 Dec 2021 16:27:54 -0600

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> On Dec 13, 2021, at 16:20, Jim Stone <[email-masked]> wrote:
>=20
> =EF=BB=BFThe company that installed my HVAC system a few years ago used a f=
ilter box on the return line that takes 20=E2=80=9D x 25" x 4=E2=80=9D filte=
rs, which is an unusual, and thus expensive, size - filters generally run ab=
out $25 each - that is not readily available other than online.

Is there a reason you aren=E2=80=99t using a washable, reusable filter?  Tha=
t=E2=80=99s what four inch housings are for, usually.=20

If you install two 1=E2=80=9D filters, put the cheap on as the prefilter.=20=

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<html><head><meta http-equiv=3D"content-type" content=3D"text/html; charset=3D=
utf-8"></head><body dir=3D"auto"><div dir=3D"ltr"><br></div><div dir=3D"ltr"=
><br><blockquote type=3D"cite">On Dec 13, 2021, at 16:20, Jim Stone &lt;1789=
[email-masked]&gt; wrote:<br><br></blockquote></div><blockquote type=3D"ci=
te"><div dir=3D"ltr">=EF=BB=BF<meta http-equiv=3D"Content-Type" content=3D"t=
ext/html; charset=3Dutf-8">The company that installed my HVAC system a few y=
ears ago used a filter box on the return line that takes 20=E2=80=9D x 25" x=
<b class=3D""> 4=E2=80=9D</b> filters, which is an unusual, and thus expensi=
ve, size - filters generally run about $25 each - that is not readily availa=
ble other than online. </div></blockquote><div><br></div><div>Is there a rea=
son you aren=E2=80=99t using a washable, reusable filter? &nbsp;That=E2=80=99=
s what four inch housings are for, usually.&nbsp;</div><div><br></div><div>I=
f you install two 1=E2=80=9D filters, put the cheap on as the prefilter.&nbs=
p;</div></body></html>=

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[email-masked]

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From: Pat Horne <[email-masked]>
Date: Mon, 13 Dec 2021 16:32:22 -0600

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My shop air handler is set up to use a 2=E2=80=9D filter but the installer s=
aid to use 2 one inch filters, both good ones. I watch the first one & remov=
e it when it is too dirty, move the second one up & install a new second one=
.=20
There is some discoloration on the second filter, so it is doing something.=20=

If you want to go with two different ones, I=E2=80=99d put the poorer one fi=
rst, followed by the better one.=20

My HVAC guy says to not use the corrugated filters, nor the fiberglass ones t=
hat you can see throughout. He sells me Purolator 312 filters by the case.=20=

Peace,
Pat

Pat Horne=20
We support Habitat for Humanity

On Dec 13, 2021, at 4:21 PM, Jim Stone <[email-masked]> wrote:

=EF=BB=BFThe company that installed my HVAC system a few years ago used a fi=
lter box on the return line that takes 20=E2=80=9D x 25" x 4=E2=80=9D filter=
s, which is an unusual, and thus expensive, size - filters generally run abo=
ut $25 each - that is not readily available other than online.  During const=
ruction, my general contractor just had a cheap 20=E2=80=9D x 25" x 1=E2=80=9D=
 filter in there that seemed to work just fine.  I checked the installation i=
nstructions for the furnace and there are no specifications for the filters,=
 other than that they need to be changed regularly, which is getting pretty e=
xpensive.  Is there any reason I couldn=E2=80=99t just use 1=E2=80=9D filter=
s, which are less than half the price?  Maybe even put two of them in the bo=
x, a good one first to catch most of the dust and a cheap one like the contr=
actor used as a secondary one.  It is a snug fit and I don=E2=80=99t think t=
here is any danger of them tipping, but two would make it impossible.

Thanks,
Jim

[email-masked]
Archive: http://www.team.net/pipermail/shop-talk http://autox.team.net/archi=
ve

[email-masked]

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<html><head><meta http-equiv=3D"content-type" content=3D"text/html; charset=3D=
utf-8"></head><body dir=3D"auto">My shop air handler is set up to use a 2=E2=
=80=9D filter but the installer said to use 2 one inch filters, both good on=
es. I watch the first one &amp; remove it when it is too dirty, move the sec=
ond one up &amp; install a new second one.&nbsp;<div>There is some discolora=
tion on the second filter, so it is doing something.&nbsp;</div><div><br></d=
iv><div>If you want to go with two different ones, I=E2=80=99d put the poore=
r one first, followed by the better one.&nbsp;</div><div><br></div><div>My H=
VAC guy says to not use the corrugated filters, nor the fiberglass ones that=
 you can see throughout. He sells me Purolator 312 filters by the case.&nbsp=
;<br><br>Peace,</div><div>Pat</div><div><br><div dir=3D"ltr">Pat Horne&nbsp;=
<div>We support Habitat for Humanity</div><div><br></div></div><div dir=3D"l=
tr"><br>On Dec 13, 2021, at 4:21 PM, Jim Stone &lt;[email-masked]&gt; w=
rote:<br><br></div><div dir=3D"ltr">=EF=BB=BF<meta http-equiv=3D"Content-Typ=
e" content=3D"text/html; charset=3Dutf-8">The company that installed my HVAC=
 system a few years ago used a filter box on the return line that takes 20=E2=
=80=9D x 25" x<b class=3D""> 4=E2=80=9D</b> filters, which is an unusual, an=
d thus expensive, size - filters generally run about $25 each - that is not r=
eadily available other than online. &nbsp;During construction, my general co=
ntractor just had a&nbsp;cheap 20=E2=80=9D x 25" x <b class=3D"">1=E2=80=9D <=
/b>filter in there that seemed to work just fine. &nbsp;I checked the instal=
lation instructions for the furnace and there are no specifications for the f=
ilters, other than that they need to be changed regularly, which is getting p=
retty expensive. &nbsp;Is there any reason I couldn=E2=80=99t just use 1=E2=80=
=9D filters, which are less than half the price? &nbsp;Maybe even put two of=
 them in the box, a good one first to catch most of the dust and a cheap one=
 like the contractor used as a secondary one. &nbsp;It is a snug fit and I d=
on=E2=80=99t think there is any danger of them tipping, but two would make i=
t impossible.<div class=3D""><br class=3D""></div><div class=3D"">Thanks,</d=
iv><div class=3D"">Jim</div><span>__________________________________________=
_____</span><br><span></span><br><span>[email-masked]</span><br><s=
pan>Donate: http://www.team.net/donate.html</span><br><span>Suggested annual=
 donation &nbsp;$12.96</span><br><span>Archive: http://www.team.net/pipermai=
l/shop-talk http://autox.team.net/archive</span><br><span></span><br><span>U=
nsubscribe/Manage: http://autox.team.net/mailman/options/shop-talk/patintexa=
[email-masked]</span><br><span></span><br></div></div></body></html>=

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[email-masked]

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From: John Innis <[email-masked]>
Date: Mon, 13 Dec 2021 16:44:10 -0600

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The only real issue is that you will not get as much airflow through a 1"
filter of a given effectiveness.  Most of the time that's not a big deal.
In our previous house we did have an issue with the AC freezing up when it
was working really hard.  In that case the solution was a lower
effectiveness filter because the box could not accommodate a thicker
filter.  If you are happy with the performance of the 1" filter and have
not had any issues, i'd say stick with it.  I do NOT recommend stacking two
one inch filters.

s, which is an
-
er in there that
e
e less than half
anger of
> http://autox.team.net/mailman/options/shop-talk/[email-masked]
>
>

--=20
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D
=3D Never offend people with style when you   =3D
=3D can offend with substance --- Sam Brown  =3D
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D

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<div dir=3D"ltr">The only real issue is that you will not get as much airfl=
ow through a 1&quot; filter of a given effectiveness.=C2=A0 Most of the tim=
e that&#39;s not a big deal.=C2=A0 In our previous house we did have an iss=
ue with the AC freezing up when it was working really hard.=C2=A0 In that c=
ase the solution was a lower effectiveness filter because the box could not=
 accommodate a thicker filter.=C2=A0 If you are happy with the performance =
of the 1&quot; filter and have not had any issues, i&#39;d say stick with i=
t.=C2=A0 I do NOT recommend stacking two one inch filters. =C2=A0<br></div>=
<br><div class=3D"gmail_quote"><div dir=3D"ltr" class=3D"gmail_attr">On Mon=
, Dec 13, 2021 at 4:20 PM Jim Stone &lt;<a href=3D"mailto:1789alpine@gmail.=
com">[email-masked]</a>&gt; wrote:<br></div><blockquote class=3D"gmai=
l_quote" style=3D"margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,20=
4,204);padding-left:1ex"><div style=3D"overflow-wrap: break-word;">The comp=
any that installed my HVAC system a few years ago used a filter box on the =
return line that takes 20=E2=80=9D x 25&quot; x<b> 4=E2=80=9D</b> filters, =
which is an unusual, and thus expensive, size - filters generally run about=
 $25 each - that is not readily available other than online.=C2=A0 During c=
onstruction, my general contractor just had a=C2=A0cheap 20=E2=80=9D x 25&q=
uot; x <b>1=E2=80=9D </b>filter in there that seemed to work just fine.=C2=
=A0 I checked the installation instructions for the furnace and there are n=
o specifications for the filters, other than that they need to be changed r=
egularly, which is getting pretty expensive.=C2=A0 Is there any reason I co=
uldn=E2=80=99t just use 1=E2=80=9D filters, which are less than half the pr=
ice?=C2=A0 Maybe even put two of them in the box, a good one first to catch=
 most of the dust and a cheap one like the contractor used as a secondary o=
ne.=C2=A0 It is a snug fit and I don=E2=80=99t think there is any danger of=
 them tipping, but two would make it impossible.<div><br></div><div>Thanks,=
</div><div>Jim</div></div>_______________________________________________<b=
r>
<br>
<a href=3D"mailto:[email-masked]" target=3D"_blank">Shop-talk@aut=
ox.team.net</a><br>
et=3D"_blank">http://www.team.net/donate.html</a><br>
Archive: <a href=3D"http://www.team.net/pipermail/shop-talk" rel=3D"norefer=
rer" target=3D"_blank">http://www.team.net/pipermail/shop-talk</a> <a href=
=3D"http://autox.team.net/archive" rel=3D"noreferrer" target=3D"_blank">htt=
p://autox.team.net/archive</a><br>
<br>
alk/[email-masked]" rel=3D"noreferrer" target=3D"_blank">http://autox.te=
am.net/mailman/options/shop-talk/[email-masked]</a><br>
<br>
</blockquote></div><br clear=3D"all"><br>-- <br><div dir=3D"ltr" class=3D"g=
mail_signature">=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D<br>=3D Never offend people with =
style when you=C2=A0=C2=A0 =3D<br>=3D can offend with substance --- Sam Bro=
wn=C2=A0 =3D<br>=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D</div>

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[email-masked]

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From: Jim Stone <[email-masked]>
Date: Mon, 13 Dec 2021 19:02:43 -0500

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Thanks, guys.  That is all good feedback. David: I hadn=E2=80=99t =
considered using a washable filter, but it is an interesting idea.  It =
looks like a 4=E2=80=9D one will cost me around $100, so the breakeven =
point is after a year.  Not too bad.

But, here is an interesting point that showed up tangentially when I =
Googled =E2=80=9Cwashable furnace filters=E2=80=9D:=20

Fortunately, most 20x25x4 air filters last between six to eight months. =
By that calculation, the average homeowners will not need more than two =
20x25x4 air filters in any given year. In contrast, a one-inch air =
filter will need to be changed every two to three months.  =
https://servicechampions.com/benefits-of-a-20x25x4-air-filter-installed-in=
-your-furnace/

If that is true, the cost difference between the 4=E2=80=9D and 1=E2=80=9D=
 disappears.  Thoughts?

Jim=20

> On Dec 13, 2021, at 5:32 PM, Pat Horne <[email-masked]> wrote:
>=20
> My shop air handler is set up to use a 2=E2=80=9D filter but the =
installer said to use 2 one inch filters, both good ones. I watch the =
first one & remove it when it is too dirty, move the second one up & =
install a new second one.=20
> There is some discoloration on the second filter, so it is doing =
something.=20
>=20
> If you want to go with two different ones, I=E2=80=99d put the poorer =
one first, followed by the better one.=20
>=20
> My HVAC guy says to not use the corrugated filters, nor the fiberglass =
ones that you can see throughout. He sells me Purolator 312 filters by =
the case.=20
> =EF=BB=BFThe company that installed my HVAC system a few years ago =
used a filter box on the return line that takes 20=E2=80=9D x 25" x 4=E2=80=
=9D filters, which is an unusual, and thus expensive, size - filters =
generally run about $25 each - that is not readily available other than =
online.  During construction, my general contractor just had a cheap =
20=E2=80=9D x 25" x 1=E2=80=9D filter in there that seemed to work just =
fine.  I checked the installation instructions for the furnace and there =
are no specifications for the filters, other than that they need to be =
changed regularly, which is getting pretty expensive.  Is there any =
reason I couldn=E2=80=99t just use 1=E2=80=9D filters, which are less =
than half the price?  Maybe even put two of them in the box, a good one =
first to catch most of the dust and a cheap one like the contractor used =
as a secondary one.  It is a snug fit and I don=E2=80=99t think there is =
any danger of them tipping, but two would make it impossible.
> Archive: http://www.team.net/pipermail/shop-talk =
> Unsubscribe/Manage: =
http://autox.team.net/mailman/options/shop-talk/[email-masked]

--Apple-Mail=_B6C3D38E-BC1C-4195-97D9-99B1563573B4
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<html><head><meta http-equiv=3D"Content-Type" content=3D"text/html; =
charset=3Dutf-8"></head><body style=3D"word-wrap: break-word; =
-webkit-nbsp-mode: space; line-break: after-white-space;" =
class=3D"">Thanks, guys. &nbsp;That is all good feedback. David: I =
hadn=E2=80=99t considered using a washable filter, but it is an =
interesting idea. &nbsp;It looks like a 4=E2=80=9D one will cost me =
around $100, so the breakeven point is after a year. &nbsp;Not too =
bad.<div class=3D""><br class=3D""></div><div class=3D"">But, here is an =
interesting point that showed up tangentially when I Googled =E2=80=9Cwash=
able furnace filters=E2=80=9D:&nbsp;</div><div class=3D""><br =
class=3D""></div><blockquote style=3D"margin: 0 0 0 40px; border: none; =
padding: 0px;" class=3D""><div class=3D""><font color=3D"#0433ff" =
class=3D""><span style=3D"caret-color: rgb(32, 33, 36); font-family: =
&quot;Google Sans Text&quot;, arial, sans-serif; background-color: =
rgb(255, 255, 255);" class=3D"">Fortunately, most 20x25x4 air filters =
last between&nbsp;</span><b style=3D"caret-color: rgb(32, 33, 36); =
font-family: &quot;Google Sans Text&quot;, arial, sans-serif;" =
class=3D"">six to eight months</b><span style=3D"caret-color: rgb(32, =
33, 36); font-family: &quot;Google Sans Text&quot;, arial, sans-serif; =
background-color: rgb(255, 255, 255);" class=3D"">. By that calculation, =
the average homeowners will not need more than two 20x25x4 air filters =
in any given year. In contrast, a one-inch air filter will need to be =
changed every two to three months. &nbsp;</span></font><a =
href=3D"https://servicechampions.com/benefits-of-a-20x25x4-air-filter-inst=
alled-in-your-furnace/" =
class=3D"">https://servicechampions.com/benefits-of-a-20x25x4-air-filter-i=
nstalled-in-your-furnace/</a></div></blockquote><div class=3D""><div><br =
class=3D""></div><div>If that is true, the cost difference between the =
4=E2=80=9D and 1=E2=80=9D disappears. &nbsp;Thoughts?</div><div><br =
class=3D""></div><div>Jim&nbsp;</div><div><br class=3D""></div><div><br =
class=3D""><blockquote type=3D"cite" class=3D""><div class=3D"">On Dec =
13, 2021, at 5:32 PM, Pat Horne &lt;<a =
href=3D"mailto:[email-masked]" =
class=3D"">[email-masked]</a>&gt; wrote:</div><br =
class=3D"Apple-interchange-newline"><div class=3D""><meta =
http-equiv=3D"content-type" content=3D"text/html; charset=3Dutf-8" =
class=3D""><div dir=3D"auto" class=3D"">My shop air handler is set up to =
use a 2=E2=80=9D filter but the installer said to use 2 one inch =
filters, both good ones. I watch the first one &amp; remove it when it =
is too dirty, move the second one up &amp; install a new second =
one.&nbsp;<div class=3D"">There is some discoloration on the second =
filter, so it is doing something.&nbsp;</div><div class=3D""><br =
class=3D""></div><div class=3D"">If you want to go with two different =
ones, I=E2=80=99d put the poorer one first, followed by the better =
one.&nbsp;</div><div class=3D""><br class=3D""></div><div class=3D"">My =
HVAC guy says to not use the corrugated filters, nor the fiberglass ones =
that you can see throughout. He sells me Purolator 312 filters by the =
case.&nbsp;<br class=3D""><br class=3D"">Peace,</div><div =
class=3D"">Pat</div><div class=3D""><br class=3D""><div dir=3D"ltr" =
class=3D"">Pat Horne&nbsp;<div class=3D"">We support Habitat for =
Humanity</div><div class=3D""><br class=3D""></div></div><div dir=3D"ltr" =
class=3D""><br class=3D"">On Dec 13, 2021, at 4:21 PM, Jim Stone &lt;<a =
href=3D"mailto:[email-masked]" =
class=3D"">[email-masked]</a>&gt; wrote:<br class=3D""><br =
class=3D""></div><div dir=3D"ltr" class=3D"">=EF=BB=BF<meta =
http-equiv=3D"Content-Type" content=3D"text/html; charset=3Dutf-8" =
class=3D"">The company that installed my HVAC system a few years ago =
used a filter box on the return line that takes 20=E2=80=9D x 25" x<b =
class=3D""> 4=E2=80=9D</b> filters, which is an unusual, and thus =
expensive, size - filters generally run about $25 each - that is not =
readily available other than online. &nbsp;During construction, my =
general contractor just had a&nbsp;cheap 20=E2=80=9D x 25" x <b =
class=3D"">1=E2=80=9D </b>filter in there that seemed to work just fine. =
&nbsp;I checked the installation instructions for the furnace and there =
are no specifications for the filters, other than that they need to be =
changed regularly, which is getting pretty expensive. &nbsp;Is there any =
reason I couldn=E2=80=99t just use 1=E2=80=9D filters, which are less =
than half the price? &nbsp;Maybe even put two of them in the box, a good =
one first to catch most of the dust and a cheap one like the contractor =
used as a secondary one. &nbsp;It is a snug fit and I don=E2=80=99t =
think there is any danger of them tipping, but two would make it =
impossible.<div class=3D""><br class=3D""></div><div =
class=3D"">Thanks,</div><div class=3D"">Jim</div><span =
class=3D"">_______________________________________________</span><br =
class=3D""><span class=3D""></span><br class=3D""><span class=3D""><a =
href=3D"mailto:[email-masked]" =
class=3D"">[email-masked]</a></span><br class=3D""><span =
class=3D"">Donate: <a href=3D"http://www.team.net/donate.html" =
class=3D"">http://www.team.net/donate.html</a></span><br class=3D""><span =
class=3D"">Suggested annual donation &nbsp;$12.96</span><br =
class=3D""><span class=3D"">Archive: <a =
href=3D"http://www.team.net/pipermail/shop-talk" =
class=3D"">http://www.team.net/pipermail/shop-talk</a> <a =
href=3D"http://autox.team.net/archive" =
class=3D"">http://autox.team.net/archive</a></span><br class=3D""><span =
class=3D""></span><br class=3D""><span class=3D"">Unsubscribe/Manage: <a =
href=3D"http://autox.team.net/mailman/options/shop-talk/patintexas@icloud.=
com" =
class=3D"">http://autox.team.net/mailman/options/shop-talk/patintexas@iclo=
ud.com</a></span><br class=3D""><span class=3D""></span><br =
class=3D""></div></div></div></div></blockquote></div><br =
class=3D""></div></body></html>=

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[email-masked]

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---

From: Jeff Scarbrough <[email-masked]>
Date: Mon, 13 Dec 2021 19:22:44 -0500

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I have a deep filter housing (this kind
https://shop.aprilaire.com/products/aprilaire-401-replacement-filter  ) and
I get a year or more out of them.  They are MERV 10, and the system is
designed for them.  A deeper filter has more surface area, so it can
collect more dust before restricting air flow.

I'm kind of in the filter business, as I help manage a high-containment
biological research laboratory where keeping things in their place is very
important.  We have hundreds of HEPA filters, plus the gamut of regular and
bag filters from MERV 8 to MERV 13.  In general, we determine when
replacement is necessary by measuring pressure drop across the filter.

I don't do that at home, but you all have got me to thinking I should. I'm
general, though, the performance of the system will inform you.  Too much
restriction (from a loaded filter, or just too many of them in the train)
will eventually cause noticable problems.

On Mon, Dec 13, 2021, 19:03 Jim Stone <[email-masked]> wrote:

> Thanks, guys.  That is all good feedback. David: I hadn=E2=80=99t conside=
red using
> a washable filter, but it is an interesting idea.  It looks like a 4=E2=
=80=9D one
> will cost me around $100, so the breakeven point is after a year.  Not to=
o
> bad.
>
> But, here is an interesting point that showed up tangentially when I
> Googled =E2=80=9Cwashable furnace filters=E2=80=9D:
>
> Fortunately, most 20x25x4 air filters last between *six to eight months*.
> By that calculation, the average homeowners will not need more than two
> 20x25x4 air filters in any given year. In contrast, a one-inch air filter
> will need to be changed every two to three months.
> https://servicechampions.com/benefits-of-a-20x25x4-air-filter-installed-i=
n-your-furnace/
>
>
> If that is true, the cost difference between the 4=E2=80=9D and 1=E2=80=
=9D disappears.
> Thoughts?
> My shop air handler is set up to use a 2=E2=80=9D filter but the installe=
r said to
> use 2 one inch filters, both good ones. I watch the first one & remove it
> when it is too dirty, move the second one up & install a new second one.
> There is some discoloration on the second filter, so it is doing
> something.
>
> If you want to go with two different ones, I=E2=80=99d put the poorer one=
 first,
> followed by the better one.
>
> My HVAC guy says to not use the corrugated filters, nor the fiberglass
> ones that you can see throughout. He sells me Purolator 312 filters by th=
e
> case.
> Pat Horne
> =EF=BB=BFThe company that installed my HVAC system a few years ago used a=
 filter
s, which is an
-
er in there that
e
e less than half
anger of
> http://autox.team.net/mailman/options/shop-talk/[email-masked]
>
>

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<div dir=3D"auto">I have a deep filter housing (this kind=C2=A0<a href=3D"h=
ttps://shop.aprilaire.com/products/aprilaire-401-replacement-filter">https:=
//shop.aprilaire.com/products/aprilaire-401-replacement-filter</a>=C2=A0 ) =
and I get a year or more out of them.=C2=A0 They are MERV 10, and the syste=
m is designed for them.=C2=A0 A deeper filter has more surface area, so it =
can collect more dust before restricting air flow.<div dir=3D"auto"><br></d=
iv><div dir=3D"auto">I&#39;m kind of in the filter business, as I help mana=
ge a high-containment biological research laboratory where keeping things i=
n their place is very important.=C2=A0 We have hundreds of HEPA filters, pl=
us the gamut of regular and bag filters from MERV 8 to MERV 13.=C2=A0 In ge=
neral, we determine when replacement is necessary by measuring pressure dro=
p across the filter.=C2=A0=C2=A0</div><div dir=3D"auto"><br></div><div dir=
=3D"auto">I don&#39;t do that at home, but you all have got me to thinking =
I should. I&#39;m general, though, the performance of the system will infor=
m you.=C2=A0 Too much restriction (from a loaded filter, or just too many o=
f them in the train) will eventually cause noticable problems.=C2=A0 =C2=A0=
</div><div dir=3D"auto"><br></div><div dir=3D"auto"><br></div></div><br><di=
v class=3D"gmail_quote"><div dir=3D"ltr" class=3D"gmail_attr">On Mon, Dec 1=
3, 2021, 19:03 Jim Stone &lt;<a href=3D"mailto:[email-masked]" target=
=3D"_blank" rel=3D"noreferrer">[email-masked]</a>&gt; wrote:<br></div=
><blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1=
px #ccc solid;padding-left:1ex"><div style=3D"word-wrap:break-word;line-bre=
ak:after-white-space">Thanks, guys.=C2=A0 That is all good feedback. David:=
 I hadn=E2=80=99t considered using a washable filter, but it is an interest=
ing idea.=C2=A0 It looks like a 4=E2=80=9D one will cost me around $100, so=
 the breakeven point is after a year.=C2=A0 Not too bad.<div><br></div><div=
>But, here is an interesting point that showed up tangentially when I Googl=
ed =E2=80=9Cwashable furnace filters=E2=80=9D:=C2=A0</div><div><br></div><b=
lockquote style=3D"margin:0 0 0 40px;border:none;padding:0px"><div><font co=
lor=3D"#0433ff"><span style=3D"font-family:&quot;Google Sans Text&quot;,ari=
al,sans-serif;background-color:rgb(255,255,255)">Fortunately, most 20x25x4 =
air filters last between=C2=A0</span><b style=3D"font-family:&quot;Google S=
ans Text&quot;,arial,sans-serif">six to eight months</b><span style=3D"font=
-family:&quot;Google Sans Text&quot;,arial,sans-serif;background-color:rgb(=
255,255,255)">. By that calculation, the average homeowners will not need m=
ore than two 20x25x4 air filters in any given year. In contrast, a one-inch=
 air filter will need to be changed every two to three months. =C2=A0</span=
></font><a href=3D"https://servicechampions.com/benefits-of-a-20x25x4-air-f=
ilter-installed-in-your-furnace/" rel=3D"noreferrer noreferrer" target=3D"_=
blank">https://servicechampions.com/benefits-of-a-20x25x4-air-filter-instal=
led-in-your-furnace/</a></div></blockquote><div><div><br></div><div>If that=
 is true, the cost difference between the 4=E2=80=9D and 1=E2=80=9D disappe=
ars.=C2=A0 Thoughts?</div><div><br></div><div>Jim=C2=A0</div><div><br></div=
><div><br><blockquote type=3D"cite"><div>On Dec 13, 2021, at 5:32 PM, Pat H=
orne &lt;<a href=3D"mailto:[email-masked]" rel=3D"noreferrer norefer=
rer" target=3D"_blank">[email-masked]</a>&gt; wrote:</div><br><div><=
div dir=3D"auto">My shop air handler is set up to use a 2=E2=80=9D filter b=
ut the installer said to use 2 one inch filters, both good ones. I watch th=
e first one &amp; remove it when it is too dirty, move the second one up &a=
mp; install a new second one.=C2=A0<div>There is some discoloration on the =
second filter, so it is doing something.=C2=A0</div><div><br></div><div>If =
you want to go with two different ones, I=E2=80=99d put the poorer one firs=
t, followed by the better one.=C2=A0</div><div><br></div><div>My HVAC guy s=
ays to not use the corrugated filters, nor the fiberglass ones that you can=
 see throughout. He sells me Purolator 312 filters by the case.=C2=A0<br><b=
r>Peace,</div><div>Pat</div><div><br><div dir=3D"ltr">Pat Horne=C2=A0<div>W=
e support Habitat for Humanity</div><div><br></div></div><div dir=3D"ltr"><=
br>On Dec 13, 2021, at 4:21 PM, Jim Stone &lt;<a href=3D"mailto:1789alpine@=
gmail.com" rel=3D"noreferrer noreferrer" target=3D"_blank">1789alpine@gmail=
.com</a>&gt; wrote:<br><br></div><div dir=3D"ltr">=EF=BB=BFThe company that=
 installed my HVAC system a few years ago used a filter box on the return l=
ine that takes 20=E2=80=9D x 25&quot; x<b> 4=E2=80=9D</b> filters, which is=
 an unusual, and thus expensive, size - filters generally run about $25 eac=
h - that is not readily available other than online.=C2=A0 During construct=
ion, my general contractor just had a=C2=A0cheap 20=E2=80=9D x 25&quot; x <=
b>1=E2=80=9D </b>filter in there that seemed to work just fine.=C2=A0 I che=
cked the installation instructions for the furnace and there are no specifi=
cations for the filters, other than that they need to be changed regularly,=
 which is getting pretty expensive.=C2=A0 Is there any reason I couldn=E2=
=80=99t just use 1=E2=80=9D filters, which are less than half the price?=C2=
=A0 Maybe even put two of them in the box, a good one first to catch most o=
f the dust and a cheap one like the contractor used as a secondary one.=C2=
=A0 It is a snug fit and I don=E2=80=99t think there is any danger of them =
tipping, but two would make it impossible.<div><br></div><div>Thanks,</div>=
<div>Jim</div><span>_______________________________________________</span><=
br><span></span><br><span><a href=3D"mailto:[email-masked]" rel=
=3D"noreferrer noreferrer" target=3D"_blank">[email-masked]</a></=
span><br><span>Donate: <a href=3D"http://www.team.net/donate.html" rel=3D"n=
oreferrer noreferrer" target=3D"_blank">http://www.team.net/donate.html</a>=
</span><br><span>Suggested annual donation =C2=A0$12.96</span><br><span>Arc=
hive: <a href=3D"http://www.team.net/pipermail/shop-talk" rel=3D"noreferrer=
 noreferrer" target=3D"_blank">http://www.team.net/pipermail/shop-talk</a> =
<a href=3D"http://autox.team.net/archive" rel=3D"noreferrer noreferrer" tar=
get=3D"_blank">http://autox.team.net/archive</a></span><br><span></span><br=
><span>Unsubscribe/Manage: <a href=3D"http://autox.team.net/mailman/options=
/shop-talk/[email-masked]" rel=3D"noreferrer noreferrer" target=3D"_=
blank">http://autox.team.net/mailman/options/shop-talk/[email-masked]=
m</a></span><br><span></span><br></div></div></div></div></blockquote></div=
><br></div></div>_______________________________________________<br>
<br>
<a href=3D"mailto:[email-masked]" rel=3D"noreferrer noreferrer" t=
arget=3D"_blank">[email-masked]</a><br>
errer noreferrer" target=3D"_blank">http://www.team.net/donate.html</a><br>
Archive: <a href=3D"http://www.team.net/pipermail/shop-talk" rel=3D"norefer=
rer noreferrer noreferrer" target=3D"_blank">http://www.team.net/pipermail/=
shop-talk</a> <a href=3D"http://autox.team.net/archive" rel=3D"noreferrer n=
oreferrer noreferrer" target=3D"_blank">http://autox.team.net/archive</a><b=
r>
<br>
alk/[email-masked]" rel=3D"noreferrer noreferrer noreferrer" target=3D=
"_blank">http://autox.team.net/mailman/options/shop-talk/[email-masked]=
m</a><br>
<br>
</blockquote></div>

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[email-masked]

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---

From: Jack Brooks <[email-masked]>
Date: Tue, 14 Dec 2021 00:21:45 +0000

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[email-masked]

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---

From: Jim Stone <[email-masked]>
Date: Mon, 13 Dec 2021 20:10:49 -0500

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Thanks again, guys.  I had a feeling that there would be at least one =
expert on the list, but it looks like I got two, at least in the first =
couple of hours. And, they both agree!  :)

Jack: a differential meter is an interesting idea, especially given the =
cost of the bigger filters.  It certainly doesn=E2=80=99t make sense to =
replace them more frequently than necessary.  I am not a mechanical =
enginerd, just a plain old ordinary nerd.  Still, I like playing around =
with new things.  Would something like this work? =
https://www.amazon.com/Manometer-Differential-Backlight-Ventilation-Measur=
ement/dp/B07K7HT3XJ/ref=3Dasc_df_B07K7HT3XJ/?tag=3Dhyprod-20&linkCode=3Ddf=
0&hvadid=3D312099766989&hvpos=3D&hvnetw=3Dg&hvrand=3D20692614293351478&hvp=
one=3D&hvptwo=3D&hvqmt=3D&hvdev=3Dc&hvdvcmdl=3D&hvlocint=3D&hvlocphy=3D900=
4590&hvtargid=3Dpla-622729475514&psc=3D1. I=E2=80=99m thinking of =
drilling a couple of holes in the filter box and semi-permanently =
mounting it.=20

Jim

> On Dec 13, 2021, at 7:21 PM, Jack Brooks <[email-masked]> wrote:
>=20
> Bingo!  Jim hit the nail on the head.=20
> =20
> The 4 inch filter has a lower pressure drop because of overall greater =
filtration area due to all of the deep pleats. It also has a lower =
frequency of filter change out for the same reason.  Using two one inch =
filters together will impact your flow. It may not affect your =
performance noticeably, but it will change the system flow, drive up fan =
energy costs, etc. =20
>=20
> https://nordicpure.com/ <https://nordicpure.com/> seems to have a lot =
of sizes in stock and they are not too badly priced either on their =
website or Amazon.  I=E2=80=99ve used them for a while and am happy with =
them. They are available in a wide range of MERV ratings too.
> =20
> I have a differential pressure meter across my filter.  It registers =
0-0.25 inches of H2O.  I let that guide my changeout frequency, which =
often is around a year before the pressure drop indicate to me that it =
should be changed. Ok, yes, I am a Mechanical Enginerd.
>=20
> Jack
> =20
> From: Shop-talk <[email-masked]> On Behalf Of John =
Innis
> Sent: Monday, December 13, 2021 2:44 PM
> To: Jim Stone <[email-masked]>
> Cc: Shop Talk <[email-masked]>
> Subject: Re: [Shop-talk] Furnace Filters
> =20
> The only real issue is that you will not get as much airflow through a =
1" filter of a given effectiveness.  Most of the time that's not a big =
deal.  In our previous house we did have an issue with the AC freezing =
up when it was working really hard.  In that case the solution was a =
lower effectiveness filter because the box could not accommodate a =
thicker filter.  If you are happy with the performance of the 1" filter =
and have not had any issues, i'd say stick with it.  I do NOT recommend =
stacking two one inch filters. =20
> =20
> On Mon, Dec 13, 2021 at 4:20 PM Jim Stone <[email-masked] =
> The company that installed my HVAC system a few years ago used a =
filter box on the return line that takes 20=E2=80=9D x 25" x 4=E2=80=9D =
filters, which is an unusual, and thus expensive, size - filters =
> Donate: http://www.team.net/donate.html =
<http://www.team.net/donate.html>
> Archive: http://www.team.net/pipermail/shop-talk =
<http://www.team.net/pipermail/shop-talk> http://autox.team.net/archive =
<http://autox.team.net/archive>
> Unsubscribe/Manage: =
http://autox.team.net/mailman/options/shop-talk/[email-masked] =
<http://autox.team.net/mailman/options/shop-talk/[email-masked]>
>=20
>=20
> --=20
> =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D
> =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D

--Apple-Mail=_A165F18C-2D7B-44E5-833D-5F1454B05A25
Content-Transfer-Encoding: quoted-printable
	charset=utf-8

<html><head><meta http-equiv=3D"Content-Type" content=3D"text/html; =
charset=3Dutf-8"></head><body style=3D"word-wrap: break-word; =
-webkit-nbsp-mode: space; line-break: after-white-space;" =
class=3D"">Thanks again, guys. &nbsp;I had a feeling that there would be =
at least one expert on the list, but it looks like I got two, at least =
in the first couple of hours. And, they both agree! &nbsp;:)<div =
class=3D""><br class=3D""></div><div class=3D"">Jack: a differential =
meter is an interesting idea, especially given the cost of the bigger =
filters. &nbsp;It certainly doesn=E2=80=99t make sense to replace them =
more frequently than necessary. &nbsp;I am not a mechanical enginerd, =
just a plain old ordinary nerd. &nbsp;Still, I like playing around with =
new things. &nbsp;Would something like this work?&nbsp;<a =
href=3D"https://www.amazon.com/Manometer-Differential-Backlight-Ventilatio=
n-Measurement/dp/B07K7HT3XJ/ref=3Dasc_df_B07K7HT3XJ/?tag=3Dhyprod-20&amp;l=
inkCode=3Ddf0&amp;hvadid=3D312099766989&amp;hvpos=3D&amp;hvnetw=3Dg&amp;hv=
rand=3D20692614293351478&amp;hvpone=3D&amp;hvptwo=3D&amp;hvqmt=3D&amp;hvde=
v=3Dc&amp;hvdvcmdl=3D&amp;hvlocint=3D&amp;hvlocphy=3D9004590&amp;hvtargid=3D=
pla-622729475514&amp;psc=3D1" =
class=3D"">https://www.amazon.com/Manometer-Differential-Backlight-Ventila=
tion-Measurement/dp/B07K7HT3XJ/ref=3Dasc_df_B07K7HT3XJ/?tag=3Dhyprod-20&am=
p;linkCode=3Ddf0&amp;hvadid=3D312099766989&amp;hvpos=3D&amp;hvnetw=3Dg&amp=
;hvrand=3D20692614293351478&amp;hvpone=3D&amp;hvptwo=3D&amp;hvqmt=3D&amp;h=
vdev=3Dc&amp;hvdvcmdl=3D&amp;hvlocint=3D&amp;hvlocphy=3D9004590&amp;hvtarg=
id=3Dpla-622729475514&amp;psc=3D1</a>. I=E2=80=99m thinking of drilling =
a couple of holes in the filter box and semi-permanently mounting =
it.&nbsp;</div><div class=3D""><br class=3D""></div><div class=3D"">Jim<br=
 class=3D""><div><br class=3D""><blockquote type=3D"cite" class=3D""><div =
class=3D"">On Dec 13, 2021, at 7:21 PM, Jack Brooks &lt;<a =
href=3D"mailto:[email-masked]" class=3D"">[email-masked]</a>&gt; =
wrote:</div><br class=3D"Apple-interchange-newline"><div class=3D""><meta =
charset=3D"UTF-8" class=3D""><div class=3D"WordSection1" style=3D"page: =
WordSection1; caret-color: rgb(0, 0, 0); font-family: Helvetica; =
font-size: 14px; font-style: normal; font-variant-caps: normal; =
font-weight: normal; letter-spacing: normal; text-align: start; =
text-indent: 0px; text-transform: none; white-space: normal; =
word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: =
none;"><div style=3D"margin: 0in; font-size: 11pt; font-family: Calibri, =
sans-serif;" class=3D""><span style=3D"font-size: 12pt; font-family: =
&quot;Times New Roman&quot;, serif; color: rgb(0, 32, 96);" =
class=3D"">Bingo!&nbsp; Jim hit the nail on the head.&nbsp;<o:p =
class=3D""></o:p></span></div><div style=3D"margin: 0in; font-size: =
11pt; font-family: Calibri, sans-serif;" class=3D""><span =
style=3D"font-size: 12pt; font-family: &quot;Times New Roman&quot;, =
serif; color: rgb(0, 32, 96);" class=3D""><o:p =
class=3D"">&nbsp;</o:p></span></div><div style=3D"margin: 0in; =
font-size: 11pt; font-family: Calibri, sans-serif;" class=3D""><span =
style=3D"font-size: 12pt; font-family: &quot;Times New Roman&quot;, =
serif; color: rgb(0, 32, 96);" class=3D"">The 4 inch filter has a lower =
pressure drop because of overall greater filtration area due to all of =
the deep pleats. It also has a lower frequency of filter change out for =
the same reason. &nbsp;Using two one inch filters together will impact =
your flow. It may not affect your performance noticeably, but it will =
change the system flow, drive up fan energy costs, etc.&nbsp;<span =
class=3D"Apple-converted-space">&nbsp;</span><br class=3D""><br =
class=3D""><a href=3D"https://nordicpure.com/" style=3D"color: blue; =
text-decoration: underline;" class=3D"">https://nordicpure.com/</a><span =
class=3D"Apple-converted-space">&nbsp;</span>seems to have a lot of =
sizes in stock and they are not too badly priced either on their website =
or Amazon.&nbsp; I=E2=80=99ve used them for a while and am happy with =
them. They are available in a wide range of MERV ratings too.<o:p =
class=3D""></o:p></span></div><div style=3D"margin: 0in; font-size: =
11pt; font-family: Calibri, sans-serif;" class=3D""><span =
style=3D"font-size: 12pt; font-family: &quot;Times New Roman&quot;, =
serif; color: rgb(0, 32, 96);" class=3D""><o:p =
class=3D"">&nbsp;</o:p></span></div><div style=3D"margin: 0in; =
font-size: 11pt; font-family: Calibri, sans-serif;" class=3D""><span =
style=3D"font-size: 12pt; font-family: &quot;Times New Roman&quot;, =
serif; color: rgb(0, 32, 96);" class=3D"">I have a differential pressure =
meter across my filter.&nbsp; It registers 0-0.25 inches of H<sub =
class=3D"">2</sub>O.&nbsp; I let that guide my changeout frequency, =
which often is around a year before the pressure drop indicate to me =
that it should be changed. Ok, yes, I am a Mechanical Enginerd.<o:p =
class=3D""></o:p></span></div><div style=3D"margin: 0in; font-size: =
11pt; font-family: Calibri, sans-serif;" class=3D""><span =
style=3D"font-size: 12pt; font-family: &quot;Times New Roman&quot;, =
serif; color: rgb(0, 32, 96);" class=3D""><br class=3D"">Jack<o:p =
class=3D""></o:p></span></div><div style=3D"margin: 0in; font-size: =
11pt; font-family: Calibri, sans-serif;" class=3D""><span =
style=3D"font-size: 12pt; font-family: &quot;Times New Roman&quot;, =
serif; color: rgb(0, 32, 96);" class=3D""><o:p =
class=3D"">&nbsp;</o:p></span></div><div style=3D"border-style: solid =
none none; border-top-width: 1pt; border-top-color: rgb(225, 225, 225); =
padding: 3pt 0in 0in;" class=3D""><div style=3D"margin: 0in; font-size: =
11pt; font-family: Calibri, sans-serif;" class=3D""><b =
class=3D"">From:</b><span =
class=3D"Apple-converted-space">&nbsp;</span>Shop-talk &lt;<a =
href=3D"mailto:[email-masked]" =
class=3D"">[email-masked]</a>&gt;<span =
class=3D"Apple-converted-space">&nbsp;</span><b class=3D"">On Behalf =
Of<span class=3D"Apple-converted-space">&nbsp;</span></b>John Innis<br =
class=3D""><b class=3D"">Sent:</b><span =
class=3D"Apple-converted-space">&nbsp;</span>Monday, December 13, 2021 =
2:44 PM<br class=3D""><b class=3D"">To:</b><span =
class=3D"Apple-converted-space">&nbsp;</span>Jim Stone &lt;<a =
href=3D"mailto:[email-masked]" =
class=3D"">[email-masked]</a>&gt;<br class=3D""><b =
class=3D"">Cc:</b><span class=3D"Apple-converted-space">&nbsp;</span>Shop =
Talk &lt;<a href=3D"mailto:[email-masked]" =
class=3D"">[email-masked]</a>&gt;<br class=3D""><b =
class=3D"">Subject:</b><span =
class=3D"Apple-converted-space">&nbsp;</span>Re: [Shop-talk] Furnace =
Filters<o:p class=3D""></o:p></div></div><div style=3D"margin: 0in; =
font-size: 11pt; font-family: Calibri, sans-serif;" class=3D""><o:p =
class=3D"">&nbsp;</o:p></div><div class=3D""><div style=3D"margin: 0in; =
font-size: 11pt; font-family: Calibri, sans-serif;" class=3D"">The only =
real issue is that you will not get as much airflow through a 1" filter =
of a given effectiveness.&nbsp; Most of the time that's not a big =
deal.&nbsp; In our previous house we did have an issue with the AC =
freezing up when it was working really hard.&nbsp; In that case the =
solution was a lower effectiveness filter because the box could not =
accommodate a thicker filter.&nbsp; If you are happy with the =
performance of the 1" filter and have not had any issues, i'd say stick =
with it.&nbsp; I do NOT recommend stacking two one inch filters. =
&nbsp;<o:p class=3D""></o:p></div></div><div style=3D"margin: 0in; =
font-size: 11pt; font-family: Calibri, sans-serif;" class=3D""><o:p =
class=3D"">&nbsp;</o:p></div><div class=3D""><div class=3D""><div =
style=3D"margin: 0in; font-size: 11pt; font-family: Calibri, =
sans-serif;" class=3D"">On Mon, Dec 13, 2021 at 4:20 PM Jim Stone &lt;<a =
href=3D"mailto:[email-masked]" style=3D"color: blue; =
text-decoration: underline;" class=3D"">[email-masked]</a>&gt; =
wrote:<o:p class=3D""></o:p></div></div><blockquote style=3D"border-style:=
 none none none solid; border-left-width: 1pt; border-left-color: =
rgb(204, 204, 204); padding: 0in 0in 0in 6pt; margin: 5pt 0in 5pt =
4.8pt;" class=3D""><div class=3D""><div style=3D"margin: 0in; font-size: =
11pt; font-family: Calibri, sans-serif;" class=3D"">The company that =
installed my HVAC system a few years ago used a filter box on the return =
line that takes 20=E2=80=9D x 25" x<b class=3D""><span =
class=3D"Apple-converted-space">&nbsp;</span>4=E2=80=9D</b><span =
class=3D"Apple-converted-space">&nbsp;</span>filters, which is an =
unusual, and thus expensive, size - filters generally run about $25 each =
- that is not readily available other than online.&nbsp; During =
construction, my general contractor just had a&nbsp;cheap 20=E2=80=9D x =
25" x<span class=3D"Apple-converted-space">&nbsp;</span><b =
class=3D"">1=E2=80=9D<span =
class=3D"Apple-converted-space">&nbsp;</span></b>filter in there that =
seemed to work just fine.&nbsp; I checked the installation instructions =
for the furnace and there are no specifications for the filters, other =
than that they need to be changed regularly, which is getting pretty =
expensive.&nbsp; Is there any reason I couldn=E2=80=99t just use 1=E2=80=9D=
 filters, which are less than half the price?&nbsp; Maybe even put two =
of them in the box, a good one first to catch most of the dust and a =
cheap one like the contractor used as a secondary one.&nbsp; It is a =
snug fit and I don=E2=80=99t think there is any danger of them tipping, =
but two would make it impossible.<o:p class=3D""></o:p></div><div =
class=3D""><div style=3D"margin: 0in; font-size: 11pt; font-family: =
Calibri, sans-serif;" class=3D""><o:p =
class=3D"">&nbsp;</o:p></div></div><div class=3D""><div style=3D"margin: =
0in; font-size: 11pt; font-family: Calibri, sans-serif;" =
class=3D"">Thanks,<o:p class=3D""></o:p></div></div><div class=3D""><div =
style=3D"margin: 0in; font-size: 11pt; font-family: Calibri, =
sans-serif;" class=3D"">Jim<o:p class=3D""></o:p></div></div></div><p =
class=3D"MsoNormal" style=3D"margin: 0in 0in 12pt; font-size: 11pt; =
font-family: Calibri, =
sans-serif;">_______________________________________________<br =
class=3D""><br class=3D""><a href=3D"mailto:[email-masked]" =
target=3D"_blank" style=3D"color: blue; text-decoration: underline;" =
class=3D"">[email-masked]</a><br class=3D"">Donate:<span =
class=3D"Apple-converted-space">&nbsp;</span><a =
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 blue; text-decoration: underline;" =
class=3D"">http://www.team.net/donate.html</a><br class=3D"">Suggested =
annual donation&nbsp; $12.96<br class=3D"">Archive:<span =
class=3D"Apple-converted-space">&nbsp;</span><a =
href=3D"http://www.team.net/pipermail/shop-talk" target=3D"_blank" =
style=3D"color: blue; text-decoration: underline;" =
class=3D"">http://www.team.net/pipermail/shop-talk</a><span =
class=3D"Apple-converted-space">&nbsp;</span><a =
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clear=3D"all" class=3D""><br class=3D"">--<span =
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class=3D""></o:p></div><div class=3D""><div style=3D"margin: 0in; =
font-size: 11pt; font-family: Calibri, sans-serif;" =
class=3D"">=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
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class=3D"">=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
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[email-masked]

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---

From: Brian Kemp <[email-masked]>
Date: Mon, 13 Dec 2021 19:32:17 -0800

If you have 1" filters, do a search for "air filter whistle".  It is a 
simple two piece plastic device you put in the filter that whistles when 
the filter needs to be changed.  Got mine in a kit from the local 
utility company.

Here is a description:
https://yourfilterconnection.com/blogs/help/what-is-a-furnace-filter-whistle

Caution - If you have a newer HVAC system still under warranty, you may 
be required to use the specified filter for the warranty to be valid.  
My installer made sure to point this out.  My Lennox MERV 16 filters run 
$70 each in a two pack, but last 9 months with two shedding cats.

Brian

[email-masked]

Unsubscribe/Manage: http://autox.team.net/mailman/options/shop-talk/[email-masked]

---

From: Jack Brooks <[email-masked]>
Date: Tue, 14 Dec 2021 03:44:23 +0000

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[email-masked]

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---

From: Tom Coradeschi <[email-masked]>
Date: Tue, 14 Dec 2021 06:36:54 -0500

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Now you=E2=80=99re getting to the point. Filtration efficiency is going to b=
e measured in MERV (and/or MPR, if you=E2=80=99re 3M) and should be independ=
ent of filter thickness.=20

What the 4=E2=80=9D filter buys you is (for the same filtration efficiency) l=
onger filter life, and, maybe, lower pressure drop across the filter. The $6=
4k question is: how much lower, and does it really make a difference? If you=
 do end up buying a differential pressure gage, would you be interested in r=
unning 1=E2=80=9D vs 4=E2=80=9D and reporting out what you see? You=E2=80=99=
d have to conjure up a way to seal up the duct so you get a good upstream re=
ading with the 1=E2=80=9D, I think.=20

Another ME here, albeit one who is not crazy about doing sheet metal work =E2=
=80=A6 at least not crazy enough that I see the point in going to a 4=E2=80=9D=
 filter, sans data showing it to be worth the effort. And I have a box full o=
f 1=E2=80=9D MERV 13 filters to use up - on a 3 month change cycle I am good=
 until early 2023, at this point:-)

Whatever you do, don=E2=80=99t stack 1=E2=80=9D filters. They will act like t=
wo resistors in series - your blower motor will almost certainly not respond=
 well to that.=20

Regards,

Tom Coradeschi
[email-masked]

> On Dec 13, 2021, at 7:03 PM, Jim Stone <[email-masked]> wrote:
>=20
> =EF=BB=BFThanks, guys.  That is all good feedback. David: I hadn=E2=80=99t=
 considered using a washable filter, but it is an interesting idea.  It look=
s like a 4=E2=80=9D one will cost me around $100, so the breakeven point is a=
fter a year.  Not too bad.
> But, here is an interesting point that showed up tangentially when I Googl=
ed =E2=80=9Cwashable furnace filters=E2=80=9D:=20
>=20
> Fortunately, most 20x25x4 air filters last between six to eight months. By=
 that calculation, the average homeowners will not need more than two 20x25x=
4 air filters in any given year. In contrast, a one-inch air filter will nee=
d to be changed every two to three months.  https://servicechampions.com/ben=
efits-of-a-20x25x4-air-filter-installed-in-your-furnace/
 disappears.  Thoughts?
>> My shop air handler is set up to use a 2=E2=80=9D filter but the installe=
r said to use 2 one inch filters, both good ones. I watch the first one & re=
move it when it is too dirty, move the second one up & install a new second o=
ne.=20
>> There is some discoloration on the second filter, so it is doing somethin=
g.=20
>> If you want to go with two different ones, I=E2=80=99d put the poorer one=
 first, followed by the better one.=20
>>=20
>> My HVAC guy says to not use the corrugated filters, nor the fiberglass on=
es that you can see throughout. He sells me Purolator 312 filters by the cas=
e.=20
>> =EF=BB=BFThe company that installed my HVAC system a few years ago used a=
 filter box on the return line that takes 20=E2=80=9D x 25" x 4=E2=80=9D fil=
ters, which is an unusual, and thus expensive, size - filters generally run a=
bout $25 each - that is not readily available other than online.  During con=
struction, my general contractor just had a cheap 20=E2=80=9D x 25" x 1=E2=80=
=9D filter in there that seemed to work just fine.  I checked the installati=
on instructions for the furnace and there are no specifications for the filt=
ers, other than that they need to be changed regularly, which is getting pre=
tty expensive.  Is there any reason I couldn=E2=80=99t just use 1=E2=80=9D f=
ilters, which are less than half the price?  Maybe even put two of them in t=
he box, a good one first to catch most of the dust and a cheap one like the c=
ontractor used as a secondary one.  It is a snug fit and I don=E2=80=99t thi=
nk there is any danger of them tipping, but two would make it impossible.
>> Archive: http://www.team.net/pipermail/shop-talk http://autox.team.net/ar=
chive
>>=20
>> Unsubscribe/Manage: http://autox.team.net/mailman/options/shop-talk/patin=
[email-masked]
> Archive: http://www.team.net/pipermail/shop-talk http://autox.team.net/arc=
hive
>=20
> Unsubscribe/Manage: http://autox.team.net/mailman/options/shop-talk/tjcora=
@icloud.com

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<html><head><meta http-equiv=3D"content-type" content=3D"text/html; charset=3D=
utf-8"></head><body dir=3D"auto">Now you=E2=80=99re getting to the point. Fi=
ltration efficiency is going to be measured in MERV (and/or MPR, if you=E2=80=
=99re 3M) and should be independent of filter thickness.&nbsp;<div><br></div=
><div>What the 4=E2=80=9D filter buys you is (for the same filtration effici=
ency) longer filter life, and, maybe, lower pressure drop across the filter.=
 The $64k question is: how much lower, and does it really make a difference?=
 If you do end up buying a differential pressure gage, would you be interest=
ed in running 1=E2=80=9D vs 4=E2=80=9D and reporting out what you see? You=E2=
=80=99d have to conjure up a way to seal up the duct so you get a good upstr=
eam reading with the 1=E2=80=9D, I think.&nbsp;</div><div><br></div><div>Ano=
ther ME here, albeit one who is not crazy about doing sheet metal work =E2=80=
=A6 at least not crazy enough that I see the point in going to a 4=E2=80=9D f=
ilter, sans data showing it to be worth the effort. And I have a box full of=
 1=E2=80=9D MERV 13 filters to use up - on a 3 month change cycle I am good u=
ntil early 2023, at this point:-)</div><div><br></div><div>Whatever you do, d=
on=E2=80=99t stack 1=E2=80=9D filters. They will act like two resistors in s=
eries - your blower motor will almost certainly not respond well to that.&nb=
sp;</div><div><br></div><div>Regards,</div><div><br><div dir=3D"ltr">Tom Cor=
adeschi<div>[email-masked]</div></div><div dir=3D"ltr"><br><blockquote ty=
pe=3D"cite">On Dec 13, 2021, at 7:03 PM, Jim Stone &lt;[email-masked]&=
gt; wrote:<br><br></blockquote></div><blockquote type=3D"cite"><div dir=3D"l=
tr">=EF=BB=BF<meta http-equiv=3D"Content-Type" content=3D"text/html; charset=
=3Dutf-8">Thanks, guys. &nbsp;That is all good feedback. David: I hadn=E2=80=
=99t considered using a washable filter, but it is an interesting idea. &nbs=
p;It looks like a 4=E2=80=9D one will cost me around $100, so the breakeven p=
oint is after a year. &nbsp;Not too bad.<div class=3D""><br class=3D""></div=
><div class=3D"">But, here is an interesting point that showed up tangential=
ly when I Googled =E2=80=9Cwashable furnace filters=E2=80=9D:&nbsp;</div><di=
v class=3D""><br class=3D""></div><blockquote style=3D"margin: 0 0 0 40px; b=
order: none; padding: 0px;" class=3D""><div class=3D""><font color=3D"#0433f=
f" class=3D""><span style=3D"caret-color: rgb(32, 33, 36); font-family: &quo=
t;Google Sans Text&quot;, arial, sans-serif; background-color: rgb(255, 255,=
 255);" class=3D"">Fortunately, most 20x25x4 air filters last between&nbsp;<=
/span><b style=3D"caret-color: rgb(32, 33, 36); font-family: &quot;Google Sa=
ns Text&quot;, arial, sans-serif;" class=3D"">six to eight months</b><span s=
tyle=3D"caret-color: rgb(32, 33, 36); font-family: &quot;Google Sans Text&qu=
ot;, arial, sans-serif; background-color: rgb(255, 255, 255);" class=3D"">. B=
y that calculation, the average homeowners will not need more than two 20x25=
x4 air filters in any given year. In contrast, a one-inch air filter will ne=
ed to be changed every two to three months. &nbsp;</span></font><a href=3D"h=
ttps://servicechampions.com/benefits-of-a-20x25x4-air-filter-installed-in-yo=
ur-furnace/" class=3D"">https://servicechampions.com/benefits-of-a-20x25x4-a=
ir-filter-installed-in-your-furnace/</a></div></blockquote><div class=3D""><=
div><br class=3D""></div><div>If that is true, the cost difference between t=
he 4=E2=80=9D and 1=E2=80=9D disappears. &nbsp;Thoughts?</div><div><br class=
=3D""></div><div>Jim&nbsp;</div><div><br class=3D""></div><div><br class=3D"=
"><blockquote type=3D"cite" class=3D""><div class=3D"">On Dec 13, 2021, at 5=
:32 PM, Pat Horne &lt;<a href=3D"mailto:[email-masked]" class=3D"">pa=
[email-masked]</a>&gt; wrote:</div><br class=3D"Apple-interchange-newli=
ne"><div class=3D""><meta http-equiv=3D"content-type" content=3D"text/html; c=
harset=3Dutf-8" class=3D""><div dir=3D"auto" class=3D"">My shop air handler i=
s set up to use a 2=E2=80=9D filter but the installer said to use 2 one inch=
 filters, both good ones. I watch the first one &amp; remove it when it is t=
oo dirty, move the second one up &amp; install a new second one.&nbsp;<div c=
lass=3D"">There is some discoloration on the second filter, so it is doing s=
omething.&nbsp;</div><div class=3D""><br class=3D""></div><div class=3D"">If=
 you want to go with two different ones, I=E2=80=99d put the poorer one firs=
t, followed by the better one.&nbsp;</div><div class=3D""><br class=3D""></d=
iv><div class=3D"">My HVAC guy says to not use the corrugated filters, nor t=
he fiberglass ones that you can see throughout. He sells me Purolator 312 fi=
lters by the case.&nbsp;<br class=3D""><br class=3D"">Peace,</div><div class=
=3D"">Pat</div><div class=3D""><br class=3D""><div dir=3D"ltr" class=3D"">Pa=
t Horne&nbsp;<div class=3D"">We support Habitat for Humanity</div><div class=
=3D""><br class=3D""></div></div><div dir=3D"ltr" class=3D""><br class=3D"">=
On Dec 13, 2021, at 4:21 PM, Jim Stone &lt;<a href=3D"mailto:1789alpine@gmai=
l.com" class=3D"">[email-masked]</a>&gt; wrote:<br class=3D""><br clas=
s=3D""></div><div dir=3D"ltr" class=3D"">=EF=BB=BF<meta http-equiv=3D"Conten=
t-Type" content=3D"text/html; charset=3Dutf-8" class=3D"">The company that i=
nstalled my HVAC system a few years ago used a filter box on the return line=
 that takes 20=E2=80=9D x 25" x<b class=3D""> 4=E2=80=9D</b> filters, which i=
s an unusual, and thus expensive, size - filters generally run about $25 eac=
h - that is not readily available other than online. &nbsp;During constructi=
on, my general contractor just had a&nbsp;cheap 20=E2=80=9D x 25" x <b class=
=3D"">1=E2=80=9D </b>filter in there that seemed to work just fine. &nbsp;I c=
hecked the installation instructions for the furnace and there are no specif=
ications for the filters, other than that they need to be changed regularly,=
 which is getting pretty expensive. &nbsp;Is there any reason I couldn=E2=80=
=99t just use 1=E2=80=9D filters, which are less than half the price? &nbsp;=
Maybe even put two of them in the box, a good one first to catch most of the=
 dust and a cheap one like the contractor used as a secondary one. &nbsp;It i=
s a snug fit and I don=E2=80=99t think there is any danger of them tipping, b=
ut two would make it impossible.<div class=3D""><br class=3D""></div><div cl=
ass=3D"">Thanks,</div><div class=3D"">Jim</div><span class=3D"">____________=
___________________________________</span><br class=3D""><span class=3D""></=
span><br class=3D""><span class=3D""><a href=3D"mailto:[email-masked].=
net" class=3D"">[email-masked]</a></span><br class=3D""><span clas=
s=3D"">Donate: <a href=3D"http://www.team.net/donate.html" class=3D"">http:/=
/www.team.net/donate.html</a></span><br class=3D""><span class=3D"">Suggeste=
d annual donation &nbsp;$12.96</span><br class=3D""><span class=3D"">Archive=
: <a href=3D"http://www.team.net/pipermail/shop-talk" class=3D"">http://www.=
team.net/pipermail/shop-talk</a> <a href=3D"http://autox.team.net/archive" c=
lass=3D"">http://autox.team.net/archive</a></span><br class=3D""><span class=
=3D""></span><br class=3D""><span class=3D"">Unsubscribe/Manage: <a href=3D"=
http://autox.team.net/mailman/options/shop-talk/[email-masked]" class=
=3D"">http://autox.team.net/mailman/options/shop-talk/[email-masked]<=
/a></span><br class=3D""><span class=3D""></span><br class=3D""></div></div>=
</div></div></blockquote></div><br class=3D""></div><span>__________________=
_____________________________</span><br><span></span><br><span>Shop-talk@aut=
ox.team.net</span><br><span>Donate: http://www.team.net/donate.html</span><b=
r><span>Suggested annual donation &nbsp;$12.96</span><br><span>Archive: http=
://www.team.net/pipermail/shop-talk http://autox.team.net/archive</span><br>=
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te></div></body></html>=

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---

From: Karl Vacek <[email-masked]>
Date: Mon, 20 Dec 2021 13:50:44 -0600

This is a multipart message in MIME format.

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The 4=E2=80=9D filter will give you far more filter area.  Generally the =
media for a given MERV rating will be about the same (differs between =
brands of course).  A thicker filter has deeper pleats, probably almost =
as many in a 1=E2=80=9D or a 4=E2=80=9D cartridge, but the 4=E2=80=9D =
will have roughly 4 times the area.  Thus a thicker filter of the same =
MERV rating will generally last as much longer as it is thicker.

=20

Remember too that the more filter area the less the pressure drop across =
the filter.  Besides blower life, the lower the pressure drop the more =
effective the filtration will be.  I used 5=E2=80=9D filters in the old =
furnace because they were the thickest that would fit.  I think they =
were about $35 apiece for 20x25.  New furnace has Carrier=E2=80=99s =
mucho-expensive air filtration system which is a box that holds a =
5=E2=80=9D filter and some electrostatic wires on the clean side.  While =
the 10-year warrantee is running I=E2=80=99ll bend over to buy theirs, =
but I doubt they=E2=80=99re anything special other than that they =
connect with a sensor in the unit that tells it that it=E2=80=99s eating =
the expensive stuff.

=20

Karl

=20

=20

=20

From: Shop-talk [mailto:[email-masked]] On Behalf Of =
Jim Stone
Sent: Monday, December 13, 2021 6:03 PM
To: Shop Talk
Subject: Re: [Shop-talk] Furnace Filters

=20

=20

=20

=20

If that is true, the cost difference between the 4=E2=80=9D and =
1=E2=80=9D disappears.  Thoughts?

=20

Jim=20

=20

=20

=20

=20

Peace,

Pat

=20

Pat Horne=20

=20

=EF=BB=BFThe company that installed my HVAC system a few years ago used =
a filter box on the return line that takes 20=E2=80=9D x 25" x =
4=E2=80=9D filters, which is an unusual, and thus expensive, size - =
filters generally run about $25 each - that is not readily available =
other than online.  During construction, my general contractor just had =
a cheap 20=E2=80=9D x 25" x 1=E2=80=9D filter in there that seemed to =
work just fine.  I checked the installation instructions for the furnace =
and there are no specifications for the filters, other than that they =
need to be changed regularly, which is getting pretty expensive.  Is =
there any reason I couldn=E2=80=99t just use 1=E2=80=9D filters, which =
are less than half the price?  Maybe even put two of them in the box, a =
good one first to catch most of the dust and a cheap one like the =
contractor used as a secondary one.  It is a snug fit and I =
don=E2=80=99t think there is any danger of them tipping, but two would =
make it impossible.

=20

Thanks,

Jim

[email-masked]

=20

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vlink=3Dpurple style=3D'word-wrap: break-word;-webkit-nbsp-mode: =
space;line-break:after-white-space'><div class=3DWordSection1><p =
class=3DMsoNormal><span =
style=3D'font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546=
A'>The 4=E2=80=9D filter will give you far more filter area.=C2=A0 =
Generally the media for a given MERV rating will be about the same =
(differs between brands of course).=C2=A0 A thicker filter has deeper =
pleats, probably almost as many in a 1=E2=80=9D or a 4=E2=80=9D =
cartridge, but the 4=E2=80=9D will have roughly 4 times the area.=C2=A0 =
Thus a thicker filter of the same MERV rating will generally last as =
much longer as it is thicker.<o:p></o:p></span></p><p =
class=3DMsoNormal><span =
style=3D'font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546=
A'><o:p>&nbsp;</o:p></span></p><p class=3DMsoNormal><span =
style=3D'font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546=
A'>Remember too that the more filter area the less the pressure drop =
across the filter.=C2=A0 Besides blower life, the lower the pressure =
drop the more effective the filtration will be.=C2=A0 I used 5=E2=80=9D =
filters in the old furnace because they were the thickest that would =
fit.=C2=A0 I think they were about $35 apiece for 20x25.=C2=A0 New =
furnace has Carrier=E2=80=99s mucho-expensive air filtration system =
which is a box that holds a 5=E2=80=9D filter and some electrostatic =
wires on the clean side.=C2=A0 While the 10-year warrantee is running =
I=E2=80=99ll bend over to buy theirs, but I doubt they=E2=80=99re =
anything special other than that they connect with a sensor in the unit =
that tells it that it=E2=80=99s eating the expensive =
stuff.<o:p></o:p></span></p><p class=3DMsoNormal><span =
style=3D'font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546=
A'><o:p>&nbsp;</o:p></span></p><p class=3DMsoNormal><span =
style=3D'font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546=
A'>Karl<o:p></o:p></span></p><p class=3DMsoNormal><span =
style=3D'font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546=
A'><o:p>&nbsp;</o:p></span></p><p class=3DMsoNormal><span =
style=3D'font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546=
A'><o:p>&nbsp;</o:p></span></p><p class=3DMsoNormal><span =
style=3D'font-size:11.0pt;font-family:"Calibri","sans-serif";color:#44546=
A'><o:p>&nbsp;</o:p></span></p><div><div =
style=3D'border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in =
0in 0in'><p class=3DMsoNormal><b><span =
style=3D'font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span>=
</b><span style=3D'font-size:10.0pt;font-family:"Tahoma","sans-serif"'> =
Shop-talk [mailto:[email-masked]] <b>On Behalf Of =
</b>Jim Stone<br><b>Sent:</b> Monday, December 13, 2021 6:03 =
PM<br><b>To:</b> Shop Talk<br><b>Subject:</b> Re: [Shop-talk] Furnace =
Filters<o:p></o:p></span></p></div></div><p =
class=3DMsoNormal><o:p>&nbsp;</o:p></p><p class=3DMsoNormal>Thanks, =
guys. &nbsp;That is all good feedback. David: I hadn=E2=80=99t =
considered using a washable filter, but it is an interesting idea. =
&nbsp;It looks like a 4=E2=80=9D one will cost me around $100, so the =
breakeven point is after a year. &nbsp;Not too =
bad.<o:p></o:p></p><div><p =
class=3DMsoNormal><o:p>&nbsp;</o:p></p></div><div><p =
class=3DMsoNormal>But, here is an interesting point that showed up =
tangentially when I Googled =E2=80=9Cwashable furnace =
filters=E2=80=9D:&nbsp;<o:p></o:p></p></div><div><p =
class=3DMsoNormal><o:p>&nbsp;</o:p></p></div><blockquote =
style=3D'margin-left:30.0pt;margin-right:0in'><div><p =
class=3DMsoNormal><span =
style=3D'font-family:"Arial","sans-serif";color:#0433FF;background:white'=
>Fortunately, most 20x25x4 air filters last between&nbsp;</span><b><span =
style=3D'font-family:"Arial","sans-serif";color:#0433FF'>six to eight =
months</span></b><span =
style=3D'font-family:"Arial","sans-serif";color:#0433FF;background:white'=
>. By that calculation, the average homeowners will not need more than =
two 20x25x4 air filters in any given year. In contrast, a one-inch air =
filter will need to be changed every two to three months. =
&nbsp;</span><a =
href=3D"https://servicechampions.com/benefits-of-a-20x25x4-air-filter-ins=
talled-in-your-furnace/">https://servicechampions.com/benefits-of-a-20x25=
x4-air-filter-installed-in-your-furnace/</a><o:p></o:p></p></div></blockq=
uote><div><div><p class=3DMsoNormal><o:p>&nbsp;</o:p></p></div><div><p =
class=3DMsoNormal>If that is true, the cost difference between the =
4=E2=80=9D and 1=E2=80=9D disappears. =
&nbsp;Thoughts?<o:p></o:p></p></div><div><p =
class=3DMsoNormal><o:p>&nbsp;</o:p></p></div><div><p =
class=3DMsoNormal>Jim&nbsp;<o:p></o:p></p></div><div><p =
class=3DMsoNormal><o:p>&nbsp;</o:p></p></div><div><p =
class=3DMsoNormal><br><br><o:p></o:p></p><div><p class=3DMsoNormal>On =
Dec 13, 2021, at 5:32 PM, Pat Horne &lt;<a =
href=3D"mailto:[email-masked]">[email-masked]</a>&gt; =
wrote:<o:p></o:p></p></div><p =
class=3DMsoNormal><o:p>&nbsp;</o:p></p><div><div><p class=3DMsoNormal>My =
shop air handler is set up to use a 2=E2=80=9D filter but the installer =
said to use 2 one inch filters, both good ones. I watch the first one =
&amp; remove it when it is too dirty, move the second one up &amp; =
install a new second one.&nbsp;<o:p></o:p></p><div><p =
class=3DMsoNormal>There is some discoloration on the second filter, so =
it is doing something.&nbsp;<o:p></o:p></p></div><div><p =
class=3DMsoNormal><o:p>&nbsp;</o:p></p></div><div><p =
class=3DMsoNormal>If you want to go with two different ones, I=E2=80=99d =
put the poorer one first, followed by the better =
one.&nbsp;<o:p></o:p></p></div><div><p =
class=3DMsoNormal><o:p>&nbsp;</o:p></p></div><div><p =
class=3DMsoNormal>My HVAC guy says to not use the corrugated filters, =
nor the fiberglass ones that you can see throughout. He sells me =
Purolator 312 filters by the =
case.&nbsp;<br><br>Peace,<o:p></o:p></p></div><div><p =
class=3DMsoNormal>Pat<o:p></o:p></p></div><div><p =
class=3DMsoNormal><o:p>&nbsp;</o:p></p><div><p class=3DMsoNormal>Pat =
Horne&nbsp;<o:p></o:p></p><div><p class=3DMsoNormal>We support Habitat =
for Humanity<o:p></o:p></p></div><div><p =
class=3DMsoNormal><o:p>&nbsp;</o:p></p></div></div><div><p =
class=3DMsoNormal style=3D'margin-bottom:12.0pt'><br>On Dec 13, 2021, at =
4:21 PM, Jim Stone &lt;<a =
href=3D"mailto:[email-masked]">[email-masked]</a>&gt; =
wrote:<o:p></o:p></p></div><div><p class=3DMsoNormal><span =
style=3D'font-family:"Tahoma","sans-serif"'>=EF=BB=BF</span>The company =
that installed my HVAC system a few years ago used a filter box on the =
return line that takes 20=E2=80=9D x 25&quot; x<b> 4=E2=80=9D</b> =
filters, which is an unusual, and thus expensive, size - filters =
generally run about $25 each - that is not readily available other than =
online. &nbsp;During construction, my general contractor just had =
a&nbsp;cheap 20=E2=80=9D x 25&quot; x <b>1=E2=80=9D </b>filter in there =
that seemed to work just fine. &nbsp;I checked the installation =
instructions for the furnace and there are no specifications for the =
filters, other than that they need to be changed regularly, which is =
getting pretty expensive. &nbsp;Is there any reason I couldn=E2=80=99t =
just use 1=E2=80=9D filters, which are less than half the price? =
&nbsp;Maybe even put two of them in the box, a good one first to catch =
most of the dust and a cheap one like the contractor used as a secondary =
one. &nbsp;It is a snug fit and I don=E2=80=99t think there is any =
danger of them tipping, but two would make it =
impossible.<o:p></o:p></p><div><p =
class=3DMsoNormal><o:p>&nbsp;</o:p></p></div><div><p =
class=3DMsoNormal>Thanks,<o:p></o:p></p></div><div><p =
class=3DMsoNormal>Jim<o:p></o:p></p></div><p class=3DMsoNormal =
style=3D'margin-bottom:12.0pt'>__________________________________________=
_____<br><br><a =
href=3D"mailto:[email-masked]">[email-masked]</a><br>=
href=3D"http://www.team.net/donate.html">http://www.team.net/donate.html<=
/a><br>Suggested annual donation &nbsp;$12.96<br>Archive: <a =
href=3D"http://www.team.net/pipermail/shop-talk">http://www.team.net/pipe=
rmail/shop-talk</a> <a =
href=3D"http://autox.team.net/archive">http://autox.team.net/archive</a><=
br><br>Unsubscribe/Manage: <a =
href=3D"http://autox.team.net/mailman/options/shop-talk/patintexas@icloud=
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om</a><o:p></o:p></p></div></div></div></div></div><p =
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