Water Heater Relief Valve

[jaaybird]

OK the water heater relief valve gushes....
I have lifted the thingy, it is very loose, and put it down gently hitting it with a hammer.

It still does not work.

I tried with a pair of pliars and channel locks, but I cannot get it off to replace. Seems like it was glued on!

What should I do?

jb

[Haffie]

Get at least a 14 inch pipe wrench to remove it. As a heater gets older, minerals in the water seems to cement the valve threads into the heater threads. If you're careful, you MIGHT be able to use a propane torch to loosen it.

Take the old one with you when purchasing a new one. There are differences in mounting, length and pressure. It's normally called a T&P valve because it can be set off by either Temperature of the water or by the Pressure generated by the heated water.

Have a good one,

Haffie

PS - IF you want to put in floor vents and a skylight, just screw a pipe plug into the valve's outlet! (Saw that on Mythbusters, heater went through all floors, out the roof and a couple hundred feet in the air.)

[jaaybird]

thanks Haffie!

[Eric J]

up what Haffie said
and even if ya was to bust the tank? so be it, its not worth anything not working, and they can be terrible tight to get to move.

mine sets alot, so I drain the tank every time I leave it, and every time I go to re-heat the tank after filling it up and gettin all the air out of it, it will pop that valve (only on the first cold tank of water tho) and every time it pops off could be the time it will not close off good again? (ya never know)
so now when i,m on that 1st heat up I let the hot water drip at the sink just a lil bit, and it has not pop-ed since.

[jaaybird]

Thanks Eric, might try that!

[drifter]

I second what Haffie said: A big pipe wrench works for me. Sometimes I have to remove the sheet metal "box" around the burner exhaust to get a good grip.

There is a special tool made just for removing those T&P valves. I don't have one but it goes over the valve and has a slot that fits over the discharge port. Last resort if the pipe wrench won't bite. I guess you'd have to get it from a plumbing supply house - never seen one at Home Depot.

[Mickey]

WOW! what a lot of pent up posts. Nothing for more than a week and now with this post from JB, all kinds of action.

JB, are you sure the valve is faulty? Could it be the valve is near the point of venting from either pressure or temp? Is there adequate air in the tank? If water logged and you then heat the water it will expand and if little/no expansion room, the valve could/will start to vent.

If it were me I'd first check on air in the tank. I may be all wet but its worth a look see.

[Haffie]

Ok.. Let's give credit where credit is due.. Addressing Mickey's point..

The water gushing from the valve, is it HOT or COLD?

If it's HOT, you probably have a bad thermostat. If it's COLD, it's the valve.

Have a good one,

Haffie

[jaaybird]

Haffie, Mickey!

Thanks

Mickey!

How do I check the air in the tank?

[Mickey]

Jay, the easy way is to use the water pump (not city water) and turn on a faucet, if little to no air, the pump will want to run most if not all the time. If there is adequate air, the pump should shut off for maybe 15 sec or so before coming back on. Lot depends upon capacity of WH.

If it has been a long time since the tank was empty, the trapped air will defuse in to the water and the tank gradually gets water logged.

If it turns out tank is water logged, when water is heated it will expand and since water is incompressible, the pressure will rise and likely trip the valve.

Now if it is the case of a water logged tank, drain all the water from the tank a then refill. To help insure complete drainage, have a hot water faucet or two open during the draining and this will insure complete draining of the tank.

I could be all wrong and valve is going bad but since it only takes a min or two and doesn't cost anything, its worth a try.

[jaaybird]

THANKS MICKEY!!!!!!!!!!!!!!!

[Russ Chastain]

Hmmm.

My water heater tank usually stays waterlogged. Since May, it's been parked in the woods with no water or power, so I've been using the water pump quite a bit.

I drained the heater tank so there would be a pocket of air inside, and it did make a difference in how the water pump acted, but it didn't last, so I just let it run.

When I turn on the water heater, I get a water leak under the sofa, near the water pump, unless I turn on the hot water tap every now and then to relieve the pressure generated by the expanding water as it heats. The leak seems to be where some flexible clear tubing is attached with a hose clamp.

This makes me wonder whether the valve on the water heater is working - or perhaps the weak spot in the plumbing is simply weaker than the valve.

On a properly working system, does the valve on the WH usually pop and leak water every time the WH is turned on without much air in the tank and the water begins to expand?

[Mickey]

Russ, the water is going to expand or contract every time the water temp changes. Not being familiar with every design, I'd be a little concerned about the cooling of the water. If water can be easily drawn in from the supply tank there should be not problem BUT if water can't be drawn in from the supply tank it would be a reason for concern. Can't stop the water from contracting and if not replaced it will reduce pressure in the plumbing and I'd be concerned over possible collapse (a small one) or creating a leak at some point.

Here is something I've thought about. If you are having problems with water logged HW tank and valve has been leaking, if the water supply has a lot of mineral content, you may have some build-up on the valve and it could leak constantly and insure water logging in short order. Don't know how easy or hard it would be to clean the mineral deposit from the valve so the fix may be to replace the valve.

[Haffie]

Heyas,

To be honest, I've never heard of air inside a HW Tank being a good thing. My reasons are as follows.

For those of you who own a "Stix-n-Brix" house and NOT on city water, go down to your basement and look at your water supply system. You'll see the pipe from your water pump going into a large blue tank. That tank is an accumulator tank and it's divided internally. The upper chamber is filled with air and set to a pressure specified by your pump manufacturer. The pump fills up the lower part of the tank, then shuts off at a pre-set pressure. When you open a faucet, water is pushed out by the AIR pressure, not the water pump. Once the pressure drops, the pump will kick in again. The accumulator has a "check valve" that prevents pressurized water from being forced out and back into the pump in the well. No where in the water system does the water com in contact with air.

In an RV, there is no accumulator UNLESS you buy a system with one built in like this...

http://www.bigdiscountrv.com/fresh-water-supplies/water-pumps/flojet-water-pumps/flojet-premium-plus-pump

The normal pump builds up to a specified pressure and then shuts off. When the pressure drops a few pounds, it kicks in again. How often this "cycling" occurs depends on the settings of the pump's pressure switch and the type of pipe in the rig. Some pipes expand more than others and act as a "pseudo" accumulator.

Using the HW heater as an accumulator would result in excess pressure in the entire system as the water heats. The heater usually doesn't have a "check valve" to prevent warm water from being pushed back out into the rest of the system, so higher pressures are put on the plumbing connections (especially that gray polybutylene pipe which was banned for home use) and the water pump itself, possibly causing leaks in older systems. Heated water might also damage the pump itself as it's components are designed for cold water use.

Air and water together in a HW heater can be extremely dangerous and might be deadly. How so? The heated water and air could allow bacterium and other nasties to multiply. You could wind up with many water borne ailments, some debilitating, some deadly, especially the longer they breed in the warm water. This is why utility companies pass out "water boil advisories" every time a line is opened for repair or service.

Next, air, water and heat accelerate corrosion. Modern cars have a closed cooling system with a overflow/recovery tank and radiator cap. As the water heats up, it's pushed out into the tank while still maintaining a closed system, as the engine and water cool, it's siphoned back into the radiator keeping the system air free. Unlike a WH, the water in your cars stays there and heat will cause the water to release minute particles of air into the system that are forced into the tank. This explains why you add coolant to the tank as fresh coolant is drawn back into the engine. Since there is always a trace of air, anti-freeze contains "anti-rust" chemicals.

Okies, that's my view on the subject, feel free to kick it around.

Have a good one,

Haffie

[Eric J]

well yall got me scratching my head a lil bit here Great topic to learn from I thinks.......

Haffie says....


To be honest, I've never heard of air inside a HW Tank being a good thing?

well I was kinda thinkin the same thing? all I have ever know it to do is hammer a water line. I have no idea if a MH water heater has a built in air pocket some how to keep a lil bit of air in there? but I do know I have checked the temp of my hot water with digital pocket thermometer just after it shut down and it was with in a few degrees of the thermostat. and most thermostats will have up to a 10 percent low or high temp for whats stamped on it? in my world of appliances anyway referring to mostly dryers. not a oven set at 350 should be dang close to 350.

My HW heater will pop every single time on that first heat up but never seem to do it again even after running out of hot water, this dont make no sense to me at all? as long as I leave a 15 to 30 sec. slow drip at the sink its never happened again, during first heat up. could be a bad pop off valve? could be its doin what its should be doin? either way I did not like the fact it was popping off inside that compartment gettin everything wet in there, so being the pop off had threads on it, I got me a lil bit of copper tubing a nut and ferrell, drilled a hole in the cover so the pipe would be exposed to the outside, (about 1 inch or less) I made it a tight fit and use a screw driver placed through the hole into the pipe to help line it up as I close the cover and have a rubber plug placed in that drain when not in use keep the bugs out. have a window right above it and you dang sure can see steem if it pops off.

One thing is fer sure, The pressure increases a good bit as it heats up.

My thoughts are (well were until I read all this) now I just dont know? ha ha but I was thinkin the reason mine popped off from a empty tank that I ran water at the tap until the air was gone, was caused by a lil bit of air still in the tank that later worked out as water was being used.
thats all that I can think of that would possibility change? i,m like in this topic tho

one thing I would do is get something to check how hot the water is just after the gas valve shuts the flame down. water is at the hottest temp right there at that time, it has been my experience with thermostats to always do at least 3 temp checks, I have seen them work correctly and than run away.