Greetings,
Like to avoid recirculation pump. Searched the archives and web but still looking for some clarification.
Copper 3/4″ main supply, 1/2″ branches in place. Pitched a little uphill as it runs.
Planning on running 1/2 return to water heater, about 50 from most distant fitting.
My question involves the height of the return relative to the supply. If these two lines are about parallel throughout the run, will the fact that the return ties into the bottom of the water heater (about 4′ lower than the “out” port) be enough to provide thermo-siphoning?
If not, how much lower does the return need to be? Supply runs above first level to serve two second level baths. Could route return maybe an inch or two lower in same joist bays. If necessary, could drop return down into basement and across to water heater but that’s problematic.
Any help would be greatly appreciated.
Todd
Replies
"...will the fact that the return ties into the bottom of the water heater...be enough to provide thermo-siphoning?"
My house is a single story with the WH in the basement. The return line comes back into the TOP of the WH, and it seems to work. I had to insulate the entire length of the supply side to get it to function, though.
I would think if you return the line to the bottom of the tank it should work fine.
How high the lines are relative to each other in the joist bays has nothing to do with how well the loop works. Only the total vertical rise matters.
Thanks, Boss. I failed physics so maybe that's why I am having trouble with the logic here. Got lots of total rise, I'll make up the return and give it a whirl.On a related note, picked up some pipe insulation at the Big Box yesterday. Sure don't make it like they used to (not very thick) but maybe I was shopping at the wrong store.Todd
"On a related note, picked up some pipe insulation at the Big Box yesterday. Sure don't make it like they used to (not very thick) but maybe I was shopping at the wrong store."
You were.