Leak from hot water heater

Replace the valve.. It's your pressure relief valve. Shouldn't leak.

Same thing you have on your typical house WH.

pressure relief valve. spring might be old or there is crud around the seal. easy enough to replace the valve

DO NOT PUT A PLUG IN THAT SPIGOT. That "spigot" is a safety valve. It is designed to leak when the pressure in the tank gets too high. It is not unusual for them to leak. Usually, after removing the red cap, you just flip the the lever a couple of times, to allow the pressure valve to reseal. Best done when thew water is cold. If it continues to leak, replace it.

Wayne

Moved to Tech.

Wayne
Moderator

And no, don't plug it. It's got threads on it so that it can be ran to a safe place (on a typical WH, it would be a head height and dangerous if it went off). But the threads are not there for a plug. If if can't blow off when things go wrong, you're WH becomes a soft grenade.

What Reddog said.

Have you tried just opening a hot spigot, like at your sink, after you turn your Hot Water on? This relieves the pressure in the tank from the heating water, which creates many of these temporary leaks, like yours.

Also, do you just turn on your hot water heater when you are going to need it, or do you turn it on at the start of a trip and leave it on during the time you are gone, until you arrive back home?

b

OK, thanks for the quick pointers. Since it appears to be common on all water heaters, I am assuming I can find the part at Home Depot?

bka0721 wrote:
Have you tried just opening a hot spigot, like at your sink, after you turn your Hot Water on? This relieves the pressure in the tank from the heating water, which creates many of these temporary leaks, like yours.

I have not tried that, but will do. Thanks.

bka0721 wrote:

Also, do you just turn on your hot water heater when you are going to need it, or do you turn it on at the start of a trip and leave it on during the time you are gone, until you arrive back home?

I usually only turn it on in the AM before or before I need it if I am going to use the shower, wash dishes, etc.

Sometimes if your water system is pressurized and you turn the heater on, the thermal expansion of the water will overpressurize your system a little and cause this to leak. Just run some hot water out of the inside faucet to lower the pressure back to normal. Or it could be some dirt caught in the seat of the relief valve. When the heater is off and the water in the tank is cold, remove the red dust cover, get a plastic bag to cover the electrical connections, stand clear of the outlet and lift up on the silver lever. This will blow some water out (probably quite forcibly) and might clear the dirt out if that is causing the problem. Or just change the safety valve for one of a similar size and pressure rating.

You never want to plug this or your water heater could explode if the thermostat fails and it overpressurizes. Mythbusters had an interesting episode on what happens if you plug the safety valve on a house water heater and then overheat the water.

I also drain and flush out my tank occasionally (usually when winterizing). It looks like you can do that with the plastic plug in the lower left of the photo.