TPR valve

Just finished with this home - it’s in great shape, but found this…that’s the top of an electric water heater. This is as close as I could get because the owners have storage shelves in front of it. How can I report this… ?

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Do you have a question?

Sorry, I was in the process of editing my post - I went back and realized it didn’t make sense. Any suggestions for wording the report?

I see a nomal install if the overpressure device at the top is permitted in your area. That device takes the place of a bladder type expansion tank.

OK - I haven’t seen this before. I just wasn’t sure if it could be tied to the TPR outlet.

More information here

That helps alot - Thanks for the info!

The TPR discharge must be separate from any other system. It appears to be tied into the other PR valve with a T-fitting.

I agree, I thought that TPR discharge had to go directly to the floor with no T-fittings at all.

Not necessarily “to the floor,” but no T-fittings are allowed in the discharge piping. . .

Yes, I skipped a bit of info didn’t I. :wink:

Direct link to the Watts installation instructions:

Not to beat you up, just like to have references, do you remember one? See “common sense” is ofen not good enough. :wink:


They may drain to outside. It should still terminate < or = to 6", or to at drain pan.


T-fittings are not specifically addressed, so the intent is somewhat subject to interpretation.

P2803.6.1 states "The discharge from the relief valve shall be piped full size separately to the floor, to the outside of the building or to an indirect waste receptor located inside the building."

So I guess one would have to ask, what is the purpose of a T-fitting?

Thanks for all the info - Jeff, I thought that was true, and it definitely connects with the other pressure valve. I’m going to write it up with your citation above and recommend it be changed.

This house is out in the boonies, with a deep well water supply.

Everyone needs to keep in mind that code requirements vary by state and even in smaller units of government within states. Check with your local AHJ for what’s acceptable in your area.

In Wisconsin plumbing is regulated by Comm 82. I have posted the relevant section below.

From WI Comm 82

(d) *Safety devices. *Water heaters shall be equipped with safety
devices as specified in this paragraph.
1. All pressurized storage−type water heaters and unfired hot
water storage tanks shall be equipped with one or more combination
temperature and pressure relief valves. The temperature
steam rating of a combination temperature and pressure relief
valve or valves shall equal or exceed the energy input rating in
BTU per hour of the water heater. No shut off valve or other
restricting device may be installed between the water heater or
storage tank and the combination temperature and pressure relief
**Note: **The temperature steam rating of a combination temperature and pressure
relief valve is commonly referred to as the AGA temperature steam rating.
2. All pressurized non−storage type water heaters shall be
provided with a pressure relief valve installed at the hot water outlet
with no shut off valve between the heater and the relief valve.
3. Temperature and pressure relief valves shall be installed so
that the sensing element of the valve extends into the heater or tank
and monitors the temperature in the top 6”of the heater or tank.
4. A vacuum relief valve shall be installed in each water
heater and hot water storage tank which, when measured from the
bottom of the heater or tank, is located more than 20 feet above any
faucet or outlet served by the heater or tank.
5. Every relief valve which is designed to discharge water or
steam shall be connected to a discharge pipe.
a. The discharge pipe and fittings shall be made of a material
acceptable for water distribution piping in accordance with s.
Comm 84.30 (4) (e) 1.
b. The discharge pipe and fittings shall have a diameter not
less than the diameter of the relief valve outlet.
c. The discharge pipe may not be trapped.
d. No valve may be installed in the discharge pipe.
e. The discharge pipe shall be installed to drain by gravity
flow to a floor served by a floor drain or to a receptor in accordance
with s. Comm 82.33(8). The outlet of the discharge pipe shall terminate
within 6”over the floor or receptor, but not less than a distance
equal to twice the diameter of the outlet pipe. The outlet of
the discharge pipe may not be threaded.
f. The discharge pipe for a water heater shall terminate within
the same room or enclosure within which the water heater or hot
water storage tank is located.

The the watts pressure regulator device in the original post would seem to be an allowed device but I have yet to see one in use. I do see expansion tanks in use on some newer construction.

I went over this with my client… I explained that there were differing opinions about the “correctness” of the T fitting, etc. I basically told them that the repair would be very cheap, and could be done quickly. For less money than a nice dinner, they would have peace of mind. I basically told them that if there ever WAS a problem, and the WH (and house) blew up, it would cost them a heck of a lot more - and they readily agreed it needed to be fixed! Nothing like putting it in perspective…!](“”)

Also check manufactures listings:D

To an approved and or acceptable discharge area. Drain line off the valve may not be elevated above the valve, (Must gravity drain away from the valve).