[Shop-talk] tankless/instant water heater

[Jim Franklin]

> On Jan 24, 2022, at 5:39 PM, David Scheidt <dmscheidt at gmail.com> wrote:
> 
> On Mon, Jan 24, 2022 at 4:27 PM john niolon <jniolon at att.net> wrote:
>> 
>> tired of just cold (really cold) water in the shop sink./..thinking about a tankless/instant water heater.  Would like to stay
>> with 120v if possible to avoid additional wiring (me crawling around in attic dragging wire with bad knees and hips.  I have an available plug
>> within 6 ' of sink
>> 
>> pros and cons ? recommendations.
>> This will strictly be a hand washing sink to be used after putting up my tools  (shop content)
>> 
> 
> an 1800W tankless water heater (the biggest you can plug into 120V
> outlet) will have a temperature rise of 25 degrees at 0.5 gpm.
> (that's the physics of water.  they're all going to have similar
> performance.  Anything that claims better is lying or has a tank)
> That will turn cold water into less cold water, or warm water into hot
> water.  you probably want something with a tank.
> 

I'm pretty sure that you can change the 120 outlet to a 240 3 prong outlet and use the existing wiring, as long as you re-wire it in the breaker box to have a 240 breaker and stay within the current limits. A dumb heater will not need a neutral so the 14/2 or 12/2 (with ground) will work unless I'm having a senior moment. 

That said I think for hand washing a 120v heater is plenty as long as you keep the flow down. Personally, I know me and I would start using it for more than hand washing, so I'd go bigger. Actually I'd get a small tank heater and insulate top & botton with rigid foam and sides with a blanket. And the pipes too. 

Let us know what you end up doing.

jim