HOME REPAIR TIPS
Plumbing: Water Heater Problems/Maintenance
Understanding the operation and maintenance of the water heater, one of the most neglected appliances in a home, can help avoid the frustration that comes when the expected hot shower becomes an icy torrent. While most water heaters—and there’s no such thing as a “hot” water heater, for HOT water wouldn’t require heating—function properly for many years with little or not attention at all, it is possible to prolong their life and improve their efficiency by taking a few simple steps.
Most—probably 99.9%—of all homeowners never look at their water heater; and most are unaware that it has an adjustable control for setting the temperature of the hot water, that it has a drain at the bottom that can be used to prolong the life of the water heater, and that by following the manufacturer’s recommendations they can both save money and avoid future problems.
If your water heater is less than two years old, periodic draining will prolong its life and improve its efficiency. What about those heaters that are more than two years old? Most plumbers tell me the sediment in the bottom has morphed into an almost solid mass and that it’s too late to begin a regular draining routine. However, water conditions vary around the country—in some areas the sediment is so thick you can spread it like peanut butter, Yuck!—but if you want to see if draining will help, go ahead.
All residential water heaters have a safety device called a pressure relief valve. The valve is located near or on the top of the water heater and keeps the tank from developing too much internal pressure. These valves should be checked periodically to make certain they function properly.
Checking the Pressure Relief Valve
First, turn off the power (for electric models) or gas (for gas fired heaters).
Turn off the cold water supply (generally a valve in one of the water lines coming out the top of the water heater).
Place a bucket under the pipe coming out of the pressure relief valve (in many homes this pipe drains outside the home).
Pull up on the lever on the pressure valve. The valve should allow hot water to escape and drain through the drain pipe attached to it. If it does not, or if it fails to seal after closing, it should be replaced. Drain the tank per the instructions below and replace the pressure relief valve.
Flushing the Water Heater
- First, turn off the power (for electric heaters) or gas (for gas fired heaters). Failure to turn off the gas or electricity could seriously damage the water heater.
- Then turn off the cold water supply.
- Connect a garden hose to the drain valve and run it to an area where it can safely drain by gravity. (The water will be very hot; don’t allow it to kill your plants or lawn, and don’t allow the hose to drain unattended to protect children, pets, or others who may be unaware of the potential for scalding)
- Open the pressure relief valve, then the drain valve where the hose is connected and allow the tank to drain completely.
- Once the tank is empty, close the drain valve, disconnect the drain hose; and close the pressure relief valve.
- Open at least one hot water faucet in the home and turn on the cold water supply to the water heater.
- Once water begins to flow from the hot water faucet, indicating the tank is full, turn on the power or gas supply to the water heater. Turning on the electricity or gas before the tank is completely full can seriously damage the water heater.
Periodically draining the tank—many plumbers recommend once every 6 months—can significantly increase the water heater’s lifespan and will allow it to operate more efficiently.