water puddle below pressure relief valve

[evergryn]

Got tired of that water puddle & residue every time I had to take the outside cover off the water heater.
First I added a brass threaded barbed fitting pointing down.
Then added few inches heater hose, a 90 degree elbow, then enough heater hose through new hole in the cover to clear by 1 or 2 inches.
No more puddle.

[pappcam]

Originally Posted by evergryn

Got tired of that water puddle & residue every time I had to take the outside cover off the water heater.
First I added a brass threaded barbed fitting pointing down.
Then added few inches heater hose, a 90 degree elbow, then enough heater hose through new hole in the cover to clear by 1 or 2 inches.
No more puddle.

Sounds like your relief valve isn't seating properly. You shouldn't have any water there.

[herk7769]

Originally Posted by pappcam

Sounds like your relief valve isn't seating properly. You shouldn't have any water there.

Yes, times 2.

You have a leaker of a valve. They are inexpensive and with a bit of teflon tape can be changed out easily.

[mtnguy]

Sometimes you can fix a leaky pressure relief valve by opening it all of the way a couple of times to remove some grit.

[evergryn]

If it was not seated properly, why would it drip out the extension I added.
I may not be a plumbing expert, but a pressure relief valve is suppose to leak when the internal tank pressure exceeds a preset value. Sort of a safety valve.

[cfsoistman]

Originally Posted by evergryn

If it was not seated properly, why would it drip out the extension I added.
I may not be a plumbing expert, but a pressure relief valve is suppose to leak when the internal tank pressure exceeds a preset value. Sort of a safety valve.

Believe me when a pressure relief valve goes you will know it. It doesn't simply drip. It opens and flows to relieve pressure at that predetermined setting. When a relief valve drips it's because it isn't seating properly. Most times it's a bit of debris that has gotten into the seal from opening it and closing it and the debris did not flush completely through. It can be as small as a grain of sand. Personally I would have pulled the valve and cleaned it and if it still leaked I would have replaced it. You've only moved your puddle to outside. Although that's better than inside.

[DAISY BOYKIN]

Two things can cause the valve to drip or leak. First you need to put a "AIR POCKET" back in the hot water tank.


#1 Turn off the water supply at the pump or faucet that your hose is
hooked to. Turn off the gas/ electricity to hot water tank.
Open the hot water faucet in the kitchen and bathroom, leave open!
Open the pressure relief valve by hand (wear gloves if water is hot).
Let drain until the water stops running or dripping.
At this time when water stops, "SNAP" close the relief valve several
times, 3-4 times, leave valve closed.
Close the hot water faucets in the kitchen and bath.
Turn water supply back on, let tank pressurise. Turn gas or electric
back on. Let water get hot ( I would use the gas to heat water for a
faster check)
After gas heat shuts off, check for any dripping, If none, you have
just saved yourself the price of a new pressure relief valve and time to install it.

#2 BUT IF IT STILL LEAKS AFTER PUTTING THE "AIR POCKET" BACK INTO
THE TANK, Procure a new relief valve, install. Follow instructions
for putting air pocket into tank.

A word of CAUTION, never open the pressure relief valve when water is
hot and UNDER PRESSURE.

If you snap open the pressure relief valve while under pressure, you will
always lose the air pocket.

[herk7769]

The "open and drain" will work to clear a calcium deposit or piece of anode if the leaker has just started. After it has leaked for a while the acid in the water will erode the seat and it will never reseat. Replacement is it.

The air pocket will always be there unless you have a leaking valve (or you open it when there is water pressure in the system) as the valve is higher than the hot water outlet. If you find yourself with no air pocket, putting one there will work only until the air seeps out and it starts leaking again. (IMO) Replace leakers.

[frankm]

Doing a little research (read: Google) about air pockets in WH came across this article. Not one to believe everything I read on the internet, this may have some truth to it. Reader beware!

RV Water Heaters - Motorhome Water Heaters

RV WATER HEATERS AND MOTORHOME WATER HEATERS

The majority of RV water heaters and motorhome water heaters are either Suburban water heaters or Atwood water heaters. RVs, which do not have Suburban or Atwood water heaters, are usually high end motor homes which may have either instantaneous water heaters or some type of engine assist water heaters. Here we’re going discuss leaking, weeping water heaters, or more specifically weeping pressure temperature relief valves. (Commonly referred to as P&T relief value)
P&T relief valves can be an area of confusion for Rv’ers until they understand the purpose and function of the P&T valve and whether or not they are functioning properly. In other words a P&T valve which is always weeping way not necessarily be bad. Let me explain why.

PURPOSE OF P&T RELIEF VALVE

RV water systems are closed systems, which mean there must be a means of relieving excess pressure when it develops. The obvious question then is what would cause excess pressure to develop in the tank. We know H2O expands when heated so we might then conclude there is always excess pressure in the water tank. This is true…only to a point however. A properly functioning RV water heater always has an air expansion pocket in the top of the tank. What is an air expansion pocket? It is simply an air pocket, which naturally forms in the water heater tank when it is filled.

As long as this air expansion pocket is of sufficient size, the only time the P&T relief water valve will weep is during the heating cycle. However, as hot water is taken from the tank the size of the air expansion pocket will diminish eventually to the point where the tank is practically full of water. When it reaches this point the inside pressure of the tank will almost always be excessive ( over the 125/150 psi rating for the P&T valve) resulting in excessive weeping of the P&T valve.

Rv’ers not aware of this may mistakenly conclude the P&T valve is bad when it is not. (Emphasis added. FM) To further complicate matters they may replace the valve and in the process re-introduce an adequate air expansion pocket and then it will naturally work fine…until the air expansion pocket is diminished again and the whole process repeats itself. Rv’ers replacing numerous P&T valves are most likely doing it needlessly. So what is the answer?

Reintroduce an adequate air expansion pocket and this is how it is done:

1. Turn water heater off.
2. Turn off water supply (city H2O or H2O pump)
3. Open closest hot H2O faucet in RV.
4. Open the P&T valve by pulling on handle at end of valve and allow H2O to flow until it stops.
5. Release handle on P&T valve – it should snap shut. ( do this a couple of times as it may stick)
6. Close hot water faucet.
7. Turn on H2O supply – Now that everything is closed the tank will refill and air expansion pocket will be re-established.
Repeat the above procedure if P&T valve continues to weep between heating cycles. If this is not successful then the P&T valve should be replaced.

[herk7769]

Frank,

That is an excellent explanation! I learn something new here all the time. I will move this to the FAQ forum.