Most water heaters share a few standard components whether it’s powered by natural gas, LP gas, oil or electricity. Generally, a shut off valve is located on the cold water feed although sometimes the valves are on both the hot and cold water supply piping.
All water heaters have a pressure and temperature relief valve. It is important that this valve functions properly. The relief valve often starts to drip with age and must be replaced. A relief valve may release sufficient quantities of water if the pressure or temperature becomes elevated so the relief valve should have a piping extension that extends to about six inches from the floor. This reduces the probability of personal contact with scalding water in the event of release.
All water heaters have a method of temperature control. Gas water heaters have a thermostat at the front lower section to allow temperature setting. Oil water heaters generally have a control on the side or front of the heater where the temperature can be adjusted but sometimes a cover must be removed. Be careful as electric wiring may become exposed with removed electric control covers. Electric heaters have temperature control thermostats under the front covers. Electric heaters have one or two thermostats, either one centrally located at the front or two, one at the top section and one at the bottom section. Again, electric wires may become exposed so be careful. Reducing the temperature from a standard 120 degrees to 110 degrees allows sufficient temperature however the quantity will be reduced as the hot water will be mixed with less cold water for delivery. Reducing the temperature also reduces stress on the tank generally allowing a longer service life.
Water heaters should be flushed or drained at least every six months. For flushing, leave the cold water supply on. Attach a garden hose to the drain valve (faucet) at the bottom of the water heater, place the other end of the hose where water will not create damage, and open the valve. Draining is performed in a similar fashion, however you shut off the cold water, open hot water faucets and the unit drains slowly. Flushing is a better method as it uses pressure to remove minerals that form in the heater to slow the heating process causing the heater to work harder to create the hot water.
An anode rod is inserted inside the heater through a threaded connection at the top of the heater. This rod is present to help control minerals in the heater. The rods do wear out and should be replaced, usually annually.
Inspect all exhaust connections, elbows, and piping for rust and secure connections. Replace all rusted sections immediately as this is a source of carbon monoxide. Insure the piping slopes upward to the chimney. Some water heaters vent directly outside with a fan assembly, not to a chimney, and all that exhaust piping should be also be checked. Open a hot water faucet to allow the temperature in the unit to drop and the fan will come on. Listen to the fan operation to insure no unusual noises occur during operation.
A gas valve is located at the front lower section of the water heater. A knob is on top of the gas valve with three positions, on, off and pilot. With gas water heaters, the pilot light must be lit for the unit to function. A device that looks like a thin copper wire extends from the gas valve to the pilot light. This is a thermocouple. The pilot light heats the end of this component and that ”knowledge” is sent to the gas valve to remain functional. If the pilot light goes out, it must be re-lit. A knob on the gas valve must be pushed down and kept down for about a minute while the thermocouple heats up. After the unit is adequately heated, the knob is released to pop up, and turned to the on position. Thermocouple components need to be replaced occasionally when not functioning.
Oil guns and gas valves should be adjusted professionally and can be performed during annual season maintenance system performance while the other components can be done by handy do-it-yourselfers.
If a leak develops in the tank, it must be replaced. Leakage can rapidly escalate and cause significant damage, so if leakage occurs, replace quickly. If the unit is located in a area where uncontrolled water leakage may cause significant damage, consider placing an overflow pan (with drainage piping) under the unit to contain and control leakage.
