Heat trap for indirect water heater

Old 10-17-08, 04:57 PM
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Heat trap for indirect water heater

Hi all, I recently had a Buderus indirect hot water tank installed. Everything works great but noticed that the hot water line off the tank stays pretty hot even when there has been no draw from the tank for several hours. this seems like a waste. I know that I can insulate the pipe but I have also heard of a "heat trap" or "thermal trap" or "thermal loop".

Does anyone know exactly how this is piped into the hot water outlet and the necessary dimensions in order for it to work properly. Does adding a mixing valve change the need for one.

Photos and/or drawings would be greatly appreciated.

Thanks. Beer 4U2
Old 10-18-08, 06:04 PM
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We used to put heat traps in most tankless coil water heaters, and the way it was done was, come out from the hot outlet side of the domestic water, then go down about 12-14 inches, then loop back up to the existing piping. That's all it is.
Old 01-15-09, 08:50 PM
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sears 75 gal power miser 12 gas water heater

i just bought a sears 75 gal power miser 12 gas water heater.
it comes with 3/4" heat traps with a 1/4" flapping plastic on the inside.. a couple of questions: 1. wont the small openings result in poor hot water pressure/flow? 2.the instructions say not to solder the connections at the water heater - does this mean i should use flexible water connections - or can i presoder a 4" long pipe to the heat trap, connent to the water heater and then solder the pipe to the house lines 4" away?
3. if i use fexible water connections, does it matter whether the loop faces up or down to create a heat loss trap? thanksBeer 4U2
Old 01-27-09, 05:53 AM
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Bump! I'd like to know the awnser to this as well.. What is my best bet w/ "heat traps"? I'd hate to find out my little plastic part has collapsed in a few years.......

Is it better or even nessasary to do a "thermal loop"?
Can you explain to me how the "thermal loop" works? I can't really picture it.....

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