Test The Pressure Relief Valve On Your Water Heater

Last week, I gave you a procedure to use for draining your hot water tank. You should perform water heater maintenance annually to ensure that it operates safely and efficiently, and does not accumulate sediment that can cause your water tank to fail prematurely.

As part of your annual water heater maintenance routine, you can also test the pressure relief valve on your water heater. The pressure relief valve is a safety device that prevents the dangerous buildup of pressure in a hot water tank. If the pressure increases significantly in the tank, the relief valve is designed to let water (and pressure) escape safely. The pressure relief valve will be on or near the top of the tank and will operate in a closed position.

The pressure relief valve has a hinged handle or stem that normally sits in a flush position against the valve cover. To test the valve, lift the handle upward (or outward) to a 90° position and allow a little water to escape. The water in the tank will be pressurized and hot, so make sure everyone (and everything) is clear of the valve before you open it.

If your pressure valve normally leaks a little water, or shows signs of leaking when the valve is closed, this could indicate a problem with pressure build-up in your hot water tank. If the valve shows signs of mineralization or cannot be opened for testing or does not close properly after testing, this could indicate that the pressure-relief valve is malfunctioning. In either case, you should consult with a licensed plumber to determine the nature of the problem.

A plumber can correct either an over-pressure situation or a bad valve easily, but since the pressure relief valve is a safety device, any problems should be corrected immediately to keep your home, family and plumbing system safe! If you have a problem with the pressure relief valve on your water heater, give us a call at Boston Standard Plumbing & Heating at (617) 288-2911 anytime. We’ll be happy to examine your system for problems and make repairs if needed.