Anonymous asked in Home & GardenMaintenance & Repairs · 1 decade ago

How often will the pressure relief lift on a hot water heater and for what reason?

I saw a small puddle under the dryer and the relief pipe end was moist. I have never noticed that before. What would cause the relief to be lifting in this hot water tank? It is an electric hot water tank.

6 Answers

  • 1 decade ago
    Favorite Answer

    The pressure relief valve works on both temperature and pressure, normally it will not lift unless there is excess pressure on the system, or your temperature is set too high on the water heater.

    Sometimes if a backflow preventer has been installed, the pressure valve will lift because there is no room for expansion in your plumbing pipes and you may need to install an expansion tank. Also the valve could be old or defective and need to be replaced.

  • 1 decade ago

    I hope you mean you found a puddle under the water heater not the dryer. I the puddle was in fact directly below the "Water Heater Pressure Relief Valve" the puddle may be just condensation.

    It should never "Pop". This is a sign of a problem needing to be addressed.

    If the valve pops you must reset it to the closed position. If the water pressure builds up in the tank high enough to pop that valve...the water is over heating or "super heating"...turn the temp down. If turning the temp down doesn't work the valve is bad, change it out.

    There should be a pipe connected to that valve so any water escaping ( in a ranging gush of HOT steam and water) will be diverted to a safe place so as not to injure person or property!

    A moist spot on the floor doesn't indicate that the valve popped, a large puddle does.

  • 1 decade ago

    Temp. and pressure cause the valve to open. The cheepest thing to do first is replace the valve (sold at all hardware and home centers. Turn the heater off, partially empty the tank and replace the valve. If this doesn't solve the problem you can replace the thermostat but if the heater is near 10 or older it is better to replace it. If it is gas the thermostat is going to be expensive anyway so just replace the heater. Think about tankless heaters. They will save gas and are better for the environment. They are more expensive but you WILL get your money back.

  • 1 decade ago

    Usually the pressure and temperature valve on your water heater will not lift, except maybe when you are first starting up a water heater from cold. If yours has been in service for a while and is now starting to lift, it is usually a sign that the valve is going bad and might need to be replaced.

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  • 1 decade ago

    It is a temperature/pressure relief valve. So your water pressure surged or the tank got too hot. It also might need to be replaced.

  • 1 decade ago

    normaly the pressure builds up when the thermostate gets stuck.Call a plummer or an electrician.

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