That drip, drip, drip of water from a faucet will get most anyone’s attention. It’s obvious, can be annoying, and is usually easily fixed with a washer or faucet repair kit. Water conservation as a priority has many benefits beyond just the aspect of social responsibility.
Not only can you lower your utility bill, but potentially reduce or eliminate the unwanted annoyance of mold, mildew, or wood rot (and damage). Dripping in a sink and down the drain is one thing; dripping on or near wood, or creating conditions that are conducive to mold and mildew are altogether different.
While attending a recent home inspection with a relative, we observed the hot water heater was dripping water from the pressure relief valve (down the discharge pipe) – the home inspector had made note of it, along with other plumbing issues. This was not a large release of water, just constant drips like a faucet. The prior homeowner probably didn’t give it much thought as its location was out of sight, and (not so) ‘harmlessly’ draining into the ground.
I replaced the relief valve for them, a.k.a., Temperature and Pressure Relief Valve, or T&P for short, after discharging the old one a couple of times to make sure it wasn’t just debris holding it open. Available at Lowe’s Home Improvement, the relief valve was about $15.00. It took less than 30 minutes to replace.
BTW - Follow the instructions carefully and turn off the power or fuel source before you drain the heater low enough to pull the valve. Also, copy the numbers down from the old valve (stamped/printed on a metal seal) and make sure you choose a direct replacement; there are many to choose from, with similar numbers, and each one has a profile specific to your model of hot water heater. If you are uncomfortable with this kind of repair, call a Pro.
Along with the notation of the leaking valve, the adjacent crawl space was also marked for signs of excess moisture. Could the two be related? I was curious about just how much water may have been put into the ground. I found a calculator on the U.S. Geological Survey's Water Science for Schools site that would help me calculate the discharge. Using a leaking faucet as my guide, I plugged in the numbers and was surprised by the following calculation:
Drips per day: 172,800
Liters per day: 43
Gallons (US) per day: 11
Gallons (US) per year: 4,165
Baths per year: 83
For $15 (and yes, plus labor if you called someone out to do the work), over 4,000 gallons a year of water was no longer going into the dirt. Too soon to determine if it is related to the crawl space, my gut tells me that it could easily be a factor. Time will tell as we go about addressing the other points of moisture noted in the inspection. Sidenote: One of the best investments you can make before buying a house is getting a good inspection from a qualified professional.
In many houses, you would be able to see this condition of dripping, or the sudden discharge of the valve – it’s triggered by excess temperature or pressure buildup in the hot water heater. But, for houses like mine that have what’s commonly called a Lowboy style of water heater, the unit is located in the crawl space under the home. Unless you had reason to look under the house, this condition could exist for some time without notice.
That’s why my hot water heater is plumbed to discharge outside the crawl space. Should a condition such as the above occur, I should be able to notice it as I walk about the outside of the house, and it may prevent a large discharge of water under the house (by sending the water outside the foundation).
Much like draining/flushing your hot water heater once or twice a year for sediment (follow the instructions so you don’t damage the heating elements), some manufacturers advocate discharging the relief valve at regular intervals to test it. I have heard pros and cons to this – the concern is that a perfectly good valve will get debris caught in the seal and create an unwanted leak.
If you haven’t done so already, make the inspection of the relief valve and discharge pipe a regular event. This simple walk-around could save you money, prevent damage, and contribute to better water conservation in your home.
p.s. Check the settings for the hot water temperature – in this case, when I replaced the valve, I also turned the upper element down to a lower setting. Many people turn this up thinking hotter is better. It’s not; people, especially children, are victims of hot water burns at an alarming rate. The most common recommended temperature I have seen is 120 degrees.
Great information leaking T&P valves - I'll have to reference this post.
Posted by: Reuben Saltzman | July 07, 2010 at 05:25 PM