This picture shows the TPR valve that seems to be re connected to supply. Is there a practical reason for this? Seems to be a defect to me. Is there a reasoning behind this type of set up. This is the second time I have seen this setup in my training.
It’s a Florida thing… you guys install it instead of an expansion tank.
BTW, the discharge pipe in your pic is improper. You cannot have any tees in it. Each T/PRV should have a dedicated discharge piping.
Also some of the PEX crimp rings are installed improperly.
Defer to a licensed plumber to fix.
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Thanks so much. I know it was not correct but didn’t understand the reasoning.
You will find much debate on this. What are the consequences of two pressure/temp devices sharing the same drain pipe? Obviously, many plumbers do not think it is an issue or they are trying to keep the cost/time down.
International Residential Code says they are not to join. It is also possible some local jurisdictions may allow it under some circumstances.
I personally call this out and recommend a plumber.
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Similar posts are:
- Tee Fitting on TPR Discharge Pipe - Members-Only / EMERGENCY FORUM - InterNACHI®️ Forum
- TPR valve routing question - Members-Only - InterNACHI®️ Forum
In short this seems to be a Florida thing. It would be nice to have confirmation from the AJH that the TEE fitting is locally OK. Nobody has articulated a functional problem, but it’s not done that way elsewhere.
The putative reason is scale in the tank could block the main TPR, so the secondary pressure relief valve takes over as a safety backup. The cold water creates far less scale, so the backup relief valve is less likely to be affected. (See one of my prior posts where I call out a water heater vendor requiring exactly this setup when installed in an area with scale prone water).
So in short, it seems to be a case of InterNACHI training needing to catch up, more than a defect.
As far as I can tell from here (not from Florida) it’s not an alternative to a pressure tank, but rather a secondary pressure relief point.
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The IRC calls for a device or tank. I am still trying to determine what is an acceptable device.
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I’m interested in your findings.
I don’t see how the PR can serve the same function as a tank. Assuming no check valve to the street, there’s no difference. Assuming a check valve a tank will regulate the pressure smoothly. A PR valve will dump at seemingly random times, potentially leading to shower scalding.
If a shower is operating, there is less likely chance of a pressure buildup!
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I agree.
Watts advertises their device for thermal expansion, which is similar to the device in the photo. Is this an approved device in lieu of a tank?
“Thermal Expansion” Thermal Expansion
Florida doesn’t use the IRC, it’s on the FBC.
8 out of 10 homes here have the valve, not a pressure tank, for thermal expansion.
The AHJ’s in this area allow the PRV connection on top of the water heater sharing the single drain line installed on the TPR (if you don’t agree with it or like it, you can take it up with them…).
Newer construction and recent re-pipes put the PRV at the main water line, outside, commonly found on an exterior wall.
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The latest FBC (2020) is IRC 2018 with amendments.
2014 FBC was based on IRC 2012 with amendments.
Both code cycles do not allow tees on the discharge pipe of a TPRV.
Are you telling us the local AHJ overrule the minimum standard of FBC? 
Perhaps they need to read the code better.
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Like I said, they allow it.
You don’t have to agree with the observation, “it is what it is”.
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In Florida the water loss must be OK. Would never fly here in California…
Do Florida water meters have a check valve?
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All the new ones do (dual check valve backflow preventer).
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Thanks that seems to be the answer I have gotten locally here in Walton County.