[Shop-talk] water heaters and hot water loops?

[old dirtbeard]

Hi guys,

We have a longish ranch home with seven sinks and 1 1/2" copper plumbing for 
the laterals. Short of having six demand heaters, the only way I could 
figure to deal with the long hot water delays and wasted water was a 
circulation system.

I have a circulation system on a conventional 75 gallon water heater. It has 
a small pump on a timer. I have it set to come on about 15 minutes before we 
get up on the morning and stays on until after we leave for work. It comes 
on again about when we get home and stays on until after dinner (proably 
four hours total). The pipes are well insulated and my gas bills are very 
low.

The notion is to have the hot water feed lines done in series (bathroom to 
bathroom) and to have the small diameter return line go back to the water 
heater from the furthest hot water feed.

I hear the pump click on in the morning and most times it does not require 
the water heater to kick-in to compensate for the incoming cold water 
accumulated overnight.

What this does do, however, is to provide instant hot water to all of the 
faucets where if I did not have it plumbed in, it could take many minutes of 
water running down the drain at the showers and at the bathroom sinks and at 
the kitchen sink to to get any semblence of warm water.

In a smaller or perhaps in a multi-story home, it probably is overkill. At 
my house, I will go outside and click the pump on if we are doing a load of 
dishes in the dishwasher on the weekends when the pump timer is not on.

I think it is great and believe this approach combined with some solar 
augemntation makes for a very attractive conventional solution (or perhaps 
not so conventional). I can post photos if you are interested.

best,

doug