Came home to a really wet basement floor today from a leaking T&P relief valve on our gas-fueled hot water heater. Our town had been doing water pipe flushing that morning so I thought maybe it could have something to do with that? Anywho, we turned off the flame to the heater and tried lighting the pilot again multiple times and it would not ignite. We then hooked a hose up to it to flush it out to see if there was sediment build-up and the water ran perfectly clear. We then used the pressure release valve at the top of the T&P relief valve and released some more water and now it is hardly even dripping and the water heater is still on 'off' mode.

Just curious as to whether or not this could be a result of our town flushing the pipes today? And also, if it sounds like our heater could be done for (it is 12 years old), or if it's possible that we just need to replace the T&P valve and something to do with the ignitor? We're hoping someone will be able to come look at it tomorrow. Thanks!

It may or may not be related to what the city was doing, but doesn't matter, they aren't likely to fix your water heater. Get a new T&P and replace it, very easy job and they aren't very costly. Then see what happens. If the tank itself isn't leaking and you can get the igniter to work so it heats water then I wouldn't replace the water heater. Although at 12 years age you've gotten your value out of it.

When a T&P gets that old it often has mineral deposits on it. So if it does open to let excess pressure escape then it may not seal tight when it closes after the pressure in the WH is reduced. When you remove the old T&P you can examine the temp probe that dangles from it, see how much mineral crud may be on it. That same stuff is often up on the inside of the T&P valve sealing surfaces.



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There could be more underlining problems then just replacing a t&p. Does your water heater have a thermal expansion tank installed? If so I could have failed or not charged correctly. Do you have a p.r.v on you water supply? If so what preassue is it set for?

What was it set for before it got fouled with the stuff they flushed? Possibility? Why it won't light is another story. Did the T&P relieve itself onto the gas valve?

WHY did you "turn off the flame to the heater"? Maybe you just do not know how to relight it. Working on the water lines has NOTHING to do with the pilot not lighting.

quote; Did the T&P relieve itself onto the gas valve?

IF it did then it was a terrible installation job, because the T&P opening is intentionally positioned so it CANNOT damage the gas valve, unless someone installs piping so it DOES happen.

I would replace the WH. Yesterday in the news another WH blew through the roof of one home and came down through the roof of another home maybe 400 ft away... just guessing at the 400 ft as it was a video I saw on FOX News.