A Derwood homeowner called in the morning about a 5-year-old A.O. Smith Vertex gas water heater leaking at the relief valve. Our technician was there that afternoon to install a new relief valve and add a thermal expansion tank.
The problem
The home's A.O. Smith Vertex gas tank water heater, about 5 years old, was leaking from its temperature-and-pressure (T&P) relief valve. The homeowner wanted it handled the same day.
What our technician found
A relief valve that drips is often reacting to pressure, not failing on its own. Water expands as it heats. In a home with a closed system and no expansion tank, that pressure has nowhere to go but out the relief valve. An old valve that has opened many times can also stop sealing.
What we did
- Replaced the T&P relief valve.
- Installed a thermal expansion tank.
- Piped the tank in with 3/4-inch pipe, adapters and elbows.
- Finished the same day the homeowner called.
Parts used
- Thermal expansion tank
- Temperature & pressure relief valve
- 3/4-inch pipe, male and female adapters, 90° elbows
The result
The new relief valve and expansion tank were installed the same afternoon.
Tips for Derwood homeowners
- Don't cap or plug a leaking relief valve. It's a safety device. Call a plumber.
- If you have a pressure-reducing valve or check valve on your main line, ask whether you need an expansion tank.
- Water from the relief valve pipe after a hot shower or laundry is a common sign of thermal expansion.
- A relief valve leak on a 5-year-old heater usually doesn't mean you need a new water heater. Fixing the cause is far cheaper.