hot water heater - relief valve

[BobCT]

have any of you guys had the relief valve trip on your h/w heater? Mine did and dumped all the water into the bilge as designed.

The heater is still working, I pulled the lever and it did it again. It's working fine though and I've been using it for a couple of hours.

Is there anything that would trigger this or is this an indication that it's going bad?


Bob

[alexander38]

Over heating or the spring is going bad. Stand by to spend a dollar.if you replace it look at putting a thur hull in so it can spit it over the side. Newer code.

[randyp]

I'm replacing the element in my Atwood water heater. I was reading the manual and it said that an air bubble can get trapped between the water and the top of the heater. As the water heats it expands and causes the relief valve to "blow". Not sure what yours is, but this may be the explanation. If this is the case the Atwood lit said basically "no big deal" (if you can believe that).

Either that or the thermostat is shot and needs replacing. None of these parts are all that expensive. It's a matter of getting at the damned thing in the first place!

[Big D]

Run the hot water for a while until you're sure there is no air in the system. If the problem persists, the t-stat is most likely at fault. I think these units also have a high temp cut-out switch in the circuit which should have tripped to prevent a boil over. Look for a round flat disc like a watch battery with two contacts or wires on it. I would replace it and the t-stat. Power off first!!

[alexander38]

The above post have good points. I did re-do mine this year temp switch and stuff got all the parts from ace hardware. And no the H/W is nowhere near the gas so let's not say anything about marine parts. Took the old stuff in and walked with everything for under $100.00 the biggest P.I.A. Was getting the rusted screws out.

[sehord]

Either your T&P Valve (temperature and Pressure relief Valve) is doing exactly as it should or it has failed. Most likely ot has failed. If the temperature or pressure of the tank exceed the design limitations of the tank the valve opens up to remove the hot scalding water and relieve pressure from the tank. Without it your water turns to a pressure cooker, then a bomb. Myth busters did a cool study with a 50 gallon tank with the T&P blocked off, the unit blew through the roof of he building and up over 500 feet, cool to watch on discovery chanel, bad to watch on your boat. Replace the T&P first, its cheap and easy (read big threads...)

[BobCT]

I ordered the relief valve and thermostat and will replace both. About $110 from Jamestown Industries.

Now, I wish these Trojans came with shut off valves which would make work like this easier. Maybe I'll add them at the heater while I'm doing this work.

Bob

[ready123]

If you are one of us who winterize you might find it a good time to install a bypass valve and hose setup so that one does not need to fill the tank with pink at winterize time.
I just drain and add a little pink to the tank and allow the bypass piping to flood the lines and anything else downstream... saves me a lot of pink each season.