06:05PM | 01/06/05
Member Since: 11/07/04
83 lifetime posts
The overflow pipe on our water heater seems to drip some lately which it did not do before. Does this indicate a problem, and what can we do about it? Thanks,

Jim D

11:34PM | 01/06/05
Member Since: 01/06/01
345 lifetime posts
Timbear - hi, the dripping you're seeing is a sign that your pressure relief valve on the top of the tank is starting to fail, or needs exercised. It exists to prevent the water inside the tank from getting too hot and rupturing the tank. Hopefully, your thermostats on your tank are working okay, and they're not set too high.

To exercise it, you'd open it up so hot water flows out of the overflow pipe (which is actually the drain pipe for the valve). (Before you do this, be sure there's an actual drain that'll take the water out somewhere...I've used a regular garden hose before to get the water outside the house.) When I've done mine before, I open it for 10-15 seconds, close it for 10-15 seconds, open it again, and close it again. If you still have the manual for the water heater, it may tell you specifically how to exercise it. Or, you can probably find info on a plumbing website, water heater manufacturer website, or even by talking with a sales person.

If the valve is failing, you'll need to replace it. The big box hardware stores normally carry these valves - they're pretty much a standard sized item, with the only variance being at what temperature they activate, so be sure to read the tag on your current one for its temperature rating, e.g., 150 degrees. You'll have to turn off the power and the water supply feeding the tank and drain off at least some of the water from the drain port at the bottom of the tank (which is recommended to get rid of sediment buildup anyway).

Once you've removed the old valve and installed the new valve, turn the water supply back on and let the tank refill BEFORE restoring the power to the tank. The water needs to cover the heating elements before they're re-energized or else you'll burn them out - it only takes a minute or two! - and then you'd be looking at even more work.

Let me also state I'm not a plumber, but I've replaced a few pressure relief valves, heater elements, and thermostats in my time so far. There are many others who post here who are professional plumbers and they may give you other advice on what to look for, or procedures to follow. I'd defer to their expert words. Good luck - and Happy New Year! Jim D/West Point, VA


05:40AM | 01/07/05
I agraee with Jim that you need to replace your pressure relief valve. Usually they fail as they get older and the spring weakens. However it can also mean a pressure surge. If after replacing the PRV you still have dripping then you need to look at why. This can include checking your pressure reducing valve and expansion tank if you have them.

It's interesting that Jim presumed you have an electric heater when my first presumption is gas heaters. Different parts of the country.


08:49AM | 01/07/05
Member Since: 11/07/04
83 lifetime posts
Yes in fact, it is a gas water heater. Thanks for the help, anything else I need to know since it is gas?


06:22PM | 01/07/05
You don't need as many percautions. You can leave the gas on. Move the control to pilot. Shut the cold water into the heater off,

drain out a few gallons (good luck), replace the PRV, water on, bleed air out a hot faucet and control to on.

It is sometimes difficult to get the plastic drains to shut back off. You can replace it with an extended brass one or cap of the drain (not the PRV) with a garden hose cap with hose washer.

Jim D

12:36PM | 01/08/05
Member Since: 01/06/01
345 lifetime posts
Lonny - hi, you're right - I violated the "assume" rule. I've only loooked at 1 USA-based gas water heater in the past (in Rockville, MD) and as soon as I saw it was gas, I begged off offering help on it.

When I was stationed in Turkey (December 1980-December 1982), I used a gas "Flash Heater" - very similar to a tankless system in that it didn't have a holding tank. In Ankara where I was, the landlord had it tied into the main gas line feeding the apartment so I didn't have too much fear about it. I could easily keep an eye on the pilot light and I could tell when it fired up - it made a fairly audible "whoomp" as the gas ignited. I also adjusted the pilot to make sure it burned good and strong!

However, in the Adana (near the Mediterranean Sea) area, the landlords typically used 20-pound propane bottles in the apartments - I don't know why. While I was working another criminal investigative matter one evening at Incirlik Air Base, I took a call from the Turkish police...two Americans found dead in their apartment. Apparently, they (newlywed husband/wife) had been showering and the pilot light blew out...the gas in the bottle hadn't had the smelly additive put in it that's supposed to warn you the gas is leaking. About the time they noticed it, the man was almost gone and probably died when he hit the concrete floor face-first. His wife died trying to drag his body to safety - she never cut off the gas or the water. The landlord noticed water running out from under the apartment front door, opened it to investigate, saw the bodies and called the police.

Anyway...I tend to advise those with gas heaters to consult a trained plumber - I'm just an advanced novice who's done some of his own repairs. Regards! Jim D/West Point, VA


04:54PM | 01/08/05
A value of the service is that we get to visit and live in different countries. Makes us appreciate the life we have in America. In Wichita we've had 70,000 living units go without electricity for four days. Ice storm. We've lost three people to carbon monoxide and only one to freezing.

Your information on replacing the temperature pressure relief valve is very good and I appreciate you sharing it. My area is mostly gas so I often assume based on my area. Tim could have had an oil fired heater.
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