Water heater T&P valve mounted on the side

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Water heater T&P valve mounted on the side

Author: sum (FL)

I usually have the T&P valve on the top of the water heater.

Recently I have one I changed the position to the side of the tank about 4" to 6" below the top of the tank.

Once I filled and pressurized the tank and water got hot I tested the valve by pulling the lever on the T&P valve. It works fine except when the lever was opened for the 30 seconds or so during my test, a small amount of water dripped out of the valve right where the lever was opened. Once I closed the lever no problem. If I open the lever again a few more drops. The T&P valve outlet and the piping connected to it no leak.

Is this normal for a side mounted T&P valve? I never experienced this with a top mounted one.

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Re: Water heater T&P valve mounted on the side
Author: hj (AZ) Yes, there is no seal around the stem so some water can get by it. If you are replacing a heater with the valve on top, it is possible that the side mounted T&P valve will be below the drain line connection and you CANNOT run it uphill to connect to it. Edited 1 times.
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Re: Water heater T&P valve mounted on the side
Author: packy (MA) relief valves can be mounted on the side as long as they are no lower than 6 inches from the top. one problem could arise if the plumber replaced the valve with one that has a longer probe. (100XL8) by watts would be an example.. OK for electric but on a gas heater the probe can be too close to the center flue which can falsely trip the temperature setting.
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