T&P Valve leaking slightly after drain and refill, warm to touch

[Bob Gall]

I was wondering if the t&p is supposed to drip periodically? It seemed to drip a bit during the drain and refill. It doesn't seem to be dripping now.

Does it normally drip under certain conditions, like after a drain and refill or does it normally not drip at all?

Is it supposed to be relatively warm/hot to touch?

The relief valve is connected to a copper drain line in the house. Is this normal?

Trying to figure out if I should change it out or if this is normal. Everything else seems in order with the water heater.

Thanks.

 

[WorthFlorida]

It’s doing what it’s designed to do. With a full tank of cold water and as the water heats up its needs to expand. If there is no expansion tank or a faucet was not opened, the pressure builds up and the valve opens. It’s spring loaded so it may open just slightly as the pressure builds

http://www.watts.com/pages/support/tp.asp?catId=64

 

[Sponsor]

 

[Bob Gall]

I did change out the valve because it seemed to dribble more often and when releasing pressure it seemed to spray water from release pin. I found that the old one was actually starting to corrode on the inside and likely about to fail.

Attaching files of the drain line. The only problem is that it's about parallel with the valve so run off just sits in the line and is never fully purged.

 

[Reach4]

Bob, get a water pressure gauge. It will be under $20 and maybe well under.

Check the water pressure after you use a fair amount hot water and then stop using any water for maybe 10 or 20 minutes. If the pressure is going over 100, put in that expansion tank.

 

[WorthFlorida]

That’s a bit of a hoogie way of connecting to a drain. It’s best to use a condensations drain pump. Put a straight piece of pipe to the pump at the floor and with a thin tubing run it to the drain.

https://www.homedepot.com/p/Little-...atic-Condensate-Removal-Pump-554401/204264949

 

[Dj2]

From the second picture: the way you have it now, you will have water sitting in the black connector.

I see that your wall outlet for the T&P valve is pretty high. I would move the T&P valve from the side of the WH, to the top of the WH. Then connect it to the wall outlet, with a solid copper pipe, eliminating any standing water in the discharge pipe.

 

[Jadnashua]

If the WH ever overheats (one of the two safety modes of the T&P valve), the outlet could be superheated water that will burst into steam when the pressure is released...a rubber hose is typically not rated for that. There can not be any restrictions in the lines, so connectors and the ID of the tubing/pipe may not be up to the installation instructions, either.

Unless there's a fault, the T&P valve should never open on its own. When old, and you manually open it, corrosion or mineral deposits can get caught when it opens preventing it from properly sealing again or binding on the shaft. Then, it's time to replace it. If it were to open up for overpressure, you may need to add or replace an expansion tank.