More heat trap questions

[Texas_RSA]

My question is very similar to the one asked 6 years ago. I also have a Rheems 40 gallon gas WH (22V50F1), whose supply lines I'm replacing and relocating to another wall. The guy who put in the unit originally installed a U-shaped heat trap on each line, apparently following the manual, which says (very ambiguously):

Heat Trap

For increased energy efficiency, some
water heaters have been supplied with
factory installed 3/4” NPT heat traps in
the hot outlet line and cold water inlet
line.

These heat traps may require a minimum
of one (1) 90° 3/4” NPT elbow and may
require an additional 90° 3/4” NPT elbow
or a 3/4” coupling depending on your
installation needs (emphasis mine).​

The WH inlet and outlet both seem to have these heat trap nipples. Here's the figure from the manual showing suggested heat traps (6 inch minimum drop).

Because the lines will ultimately run up to the attic, these U bends require quite a bit of extra space in what is already a fairly tight installation. If I omit these U bends, and just connect flexible lines to the planned nipples at the wall (i.e., no U, just across the top of the heater and up), what is the downside, aside from (I assume) decreased efficiency? Is that any danger?

​

 

[Reach4]

I think most WHs today come with heat traps built into their nipples.

 

[Sponsor]

 

[WorthFlorida]

Home made heat traps are not required. As Reach stated, all WH's have the nipple heat traps installed at the factory to meet EPA energy guidelines.

 

[Sylvan]

Heat traps are just good plumbing practices (see the Holby Tempering valve installation instructions )

The heat sink prevents stratification of hot water entering the CW supply (27" loop MIN ) does not fail as the piece of plastic can.

The a 6" loop accomplishes NOTHING

The heat sink is only required on the C W supply in lieu of a check valve or piece plastic /rubber that is prone to failure

https://www.holby.com/wp-content/uploads/2017/01/holby-valve-DETAIL-No-13.pdf

 

[Sylvan]

By the way this is the only brand of tempering valves I use as failure is not an option


https://www.supplyhouse.com/Holby-H...gnGFd9dgeZCKjI3uctWe88-_9gPTPms0aAinkEALw_wcB

 

[Texas_RSA]

Home made heat traps are not required. As Reach stated, all WH's have the nipple heat traps installed at the factory to meet EPA energy guidelines.

@Reach and @WorthFlorida, thanks a lot for the explainer. I was confused by the manual, which I guess (?) is trying to cover the possibility that the factory-installed heat trap nipples aren't present (I guess). Anyways, I'm glad not to have to worry about putting in extra pipe and elbows.

 

[Texas_RSA]

Heat traps are just good plumbing practices (see the Holby Tempering valve installation instructions )

The heat sink prevents stratification of hot water entering the CW supply (27" loop MIN ) does not fail as the piece of plastic can.

The a 6" loop accomplishes NOTHING

The heat sink is only required on the C W supply in lieu of a check valve or piece plastic /rubber that is prone to failure

https://www.holby.com/wp-content/uploads/2017/01/holby-valve-DETAIL-No-13.pdf

Thanks Sylvan

 

[Sylvan]

The problem with something mechanical it can fail

The heat sink is fool proof as the hot water molecules can not travel more then 27" so stratification wont happen .

This "plumber" was pointing to something other then the tempering valve which was installed improperly.

The law firm fired him and I was hired to give an expert opinion what could cause the cold water to have scalding hot temperatures

NOTICE how the tempering valve has no loop

This is a home attendant who was taking care of a very old lady and when the attendant took a shower the water spiked to over 147 DEG F

The other plumbers report was useless as he was not looking at all the deficiencies of the installation

No thermometer on the tempered water line, no test faucet to allow water water to flow and then get an accurate reading of the water being supplied