If you have a tank water heater in your home, chances are good that your only genuine contact with it is your daily shower. Most people don’t realize that water heaters require regular maintenance. Performing regular maintenance on your water heater can not only extend the life of the tank, but also ensure that you have trouble-free operation for years.
You might think of your water heater as being a giant kettle that sits in your basement or in a utility closet. The water inside never heats up enough to boil (hopefully), but the tank always keeps heated water ready to go. Your water heater is a little more complicated than that, which is why it requires regular maintenance.
If you have a conventional tank water heater, you’ll want to become familiar with the maintenance routine for your tank. If you have an older tank in service, and you’ve never performed routine maintenance on it, beginning a maintenance routine may not get you very much. The trick to prolonging the life of a hot water tank is to begin maintenance on the tank when it is brand new and continue the routine throughout the tank’s life. Knowing how a water tank operates will show you why this is the case.
A conventional water tank has an energy source – either electricity or natural gas. (Water heaters can also operate on propane or fuel oil.) It has a water inlet for the cold water supply, and a water outlet for the heated water. The tank also has a thermostat to control the water temperature, and a pressure relief valve. A gas water heater will have an exhaust vent at or near the top of the tank and a gas burner at the bottom (outside) of the tank. An electric water heater will have one or two heating elements inside the tank. The tank itself is lined with glass. There’s a drain valve at the bottom of the tank, and the tank is insulated to improve energy efficiency.
Tanks also have a “sacrificial anode” which is a magnesium rod that sits in the water and controls the rate of corrosion in the tank. If the magnesium rod weren’t there, the tank itself would begin to corrode immediately. Because its job is to corrode, the rod deteriorates over time. Once the rod has deteriorated, the tank will begin to corrode rapidly. Replacing the sacrificial rod periodically will extend the life of your tank. The tank warranty provides a good rule of thumb for changing the anode in the tank. If your tank has a 6-year warranty, change the rod every 5-6 years. If it has a 9 year warranty, change it every 7-9 years. With a 12-year warranty, change the rods every 10-12 years.
Factors other than the passage of time can affect how rapidly the sacrificial anode deteriorates. Inspecting the rod annually can better help you determine when to replace your tank’s rod.
As a side note, the deterioration of the sacrificial anode is the reason you should never consume hot water from the tap. The water becomes contaminated by the water heater and is no longer fit for consumption.
Over time, debris from the anode, minerals and corrosion build up at the bottom of the tank. If you don’t drain the debris out periodically, it will form a “blanket” at the bottom of the tank and decrease the tank’s heating efficiency. The sediment can also escape the tank and collect in your water fixtures. Draining the tank from the bottom periodically will remove the sediment. Some people prefer to run a gallon or two of heated water from the bottom of the tank regularly to keep the sediment level in check.
Your water heater also has a temperature and pressure relief valve. This valve will open if the temperature or the pressure in the tank becomes too high. You can test the valve by pulling the trip lever on it. If the valve is operating correctly, it should relieve a little water or water vapor from the tank. You may also hear a little rush of air escaping the valve. If none of these things happen, the temperature and pressure valve may have gone bad. It’s important to replace the T&P valve. Without it, your tank could experience a dangerous increase in pressure, which could lead to an explosion.
If you’d like more information about water heater maintenance, or if you would like to replace your existing water heater, please call us at Boston Standard Company at (617) 288-2911.
Photo Credit: Cole Camplese, via Flickr