Water heaters live their lives relatively out of sight, delivering hot water on demand. They need very little maintenance, but as with furnaces and AC units, occasional attention is repaid in longer life and lower running costs.
There are two types of water heaters: those with a tank and so-called “tankless” heaters. Here we'll address how to care for the more common tank type.
Understanding your water heater
The water heater comprises a tank, a heating element, and connections for cold and hot water. In addition, there's a drain valve for emptying, a thermostat for temperature control, and a pressure relief valve (T&P). Heating is done either by gas or electricity. Most tanks also have an anode rod reaching down into the water from the top. This is designed to corrode, which stops the tank itself from rusting.
Two jobs need to be done every few months: testing that the T&P is still working and draining off sediment. It's usually easiest to do them at the same time. Here's how:
- Shut off the electricity or gas so the tank doesn't heat water while you're working on it.
- Shut off the cold water supply.
- Check the T&P by operating the small lever. Air or water should be released. Make sure the flow stops when the lever is released. If not, it's time for a new valve.
- Connect a hose to the drain and open the valve. Operate the T&P so air can enter the tank and let water out. Run off a couple of gallons of water, or until it flows clear, then close the valve.
- Allow cold water back into the tank, then turn on the electricity or open the gas supply valve and light the pilot.
One additional task to consider while the water and power are off is to check the anode rod. This is removed by unscrewing a hex bolt on the top of the tank. However, as it is factory installed, it can be very difficult to release. If the rod can be taken out, check for corrosion. If it seems severe, replace with a new rod.
Heat is lost at a rate proportional to the temperature difference, which is why turning down the thermostat saves energy. In fact, lowering water temperature by 10°F can cut the water heating bill by 5 percent.
A second way of saving money on water heating is to insulate both the tank and the water pipes. Tank jackets come in many forms, and pipe insulation is available in lengths of foam pre-slit to fit over the pipe. (Insulating the cold pipe helps prevent condensation.)
Maintenance prevents problems
Water heaters generally go unnoticed until they stop working. Replacement is both costly and inconvenient, and that's why regular maintenance is worth your time.