The average water heater will last about 12 years according to industry statistics.
Sadly, far too many water heaters fail long before that. With a bit of periodic
maintenance, a water heater should last well into its teens or longer, thus,
saving you money and reducing our nation's landfill sites.
Although there are various styles of water heaters in this country, the most
popular is the tank type, which is fueled by natural gas. An electric variation
contains one or more electrical elements that heat the water. In either case,
a water heater will operate more efficiently and last longer if you perform
a few routine tasks.
The most common reason for water heater replacement is a leaking tank. Although
leaks can occur for a host of reasons, the two most common ones are sediment
buildup at the base of the tank and electrolysis. Sediment can cause excessive
temperatures that stress the tank linking, and electrolysis will result in pinhole
leaks in the tank's lining.
Remove sediment buildup at the base of the tank by flushing the tank at least
once annually and more often if you have hard water. To flush the water heater,
attach a garden hose to the drain valve at the base of the tank and run the
hose out to a location where hot water can be safely drained. Turn the valve
on and allow it to run for several minutes -- until the water becomes clear.
Since you will be dealing with hot water, be careful not to get burned.
For water heaters that have not been flushed in ages (those that might have
much sediment at the base of the tank), we suggest using a chemical additive
that will help dissolve the sediment and facilitate the flushing process. Such
a chemical can be found in the plumbing or water heater section or your local
hardware store or home-improvement center. Another excellent resource is a plumbing
supply house that sells to the trade.
Use the chemical in strict accordance with the directions on the label. Usually
the cold-water supply valve to the water heater will need to be turned off and
the supply line removed from the top of the water heater so that the solutions
can be poured into the water heater. After a time -- usually several hours --
the water heater can be flushed as described earlier.
Another sediment-busting technique that is being used by many water heater
manufacturers is a curved dip tube. The dip tube is a small-diameter plastic
pipe that carries water from the cold-water inlet at the top of the water heater
to within 12 inches or so of the base of the tank where the burners are located.
A curve at the end of the dip tube (placed at the proper angle) will create
a swirling action that will help reduce sediment buildup and assist in the flushing
Pinhole leaks in the tank lining are prevented by a cathodic or ``sacrificial''
anode that is located inside the tank. It is a vertical rod with a hex head
that runs from the top of the tank to within about a foot of the base. As its
name implies, the anode is designed to give itself up to protect the integrity
of the tank. Depending on its composition (zinc, magnesium or aluminum), the
water quality and whether you have a water softener, an anode can require replacement
as often as once a year. An anode should, however, last about three years. A
replacement anode can be found in the water heater-plumbing section of your
local hardware store or home center or at a plumbing supply store that sells
to the trade. Removal and replacement can be a daunting task that might best
Water at the base of a tank is not always the result of a leaking tank and,
thus, will not necessarily require replacement. A leaking water connection that
might not be visible at the top of the tank can trickle down the outside (inside
the outer shell of the tank) and show itself as a puddle of water on the floor
below the tank. Careful inspection of the various connections using a dry towel
and a flashlight might reveal a leak that can easily be repaired with a wrench
in a matter of seconds.
The hot- and cold-water connections at the top of the water heater usually
are made with flexible copper supply lines that are attached to the water heater
with short lengths of pipe called nipples. Brass nipples and or dielectric unions
should be used to prevent electrolysis. In addition, all pipe threads should
be wrapped with Teflon tape or a similar material that prevents leaks.
Another likely location for a leaking water heater is the temperature and
pressure relief valve (TP&R valve). The TP&R valve is a safety valve
that is designed to open when the water in the tank becomes too hot or the pressure
in the tank becomes excessive. The valve is attached to the tank by a threaded
connection. Like the water supply connections at the top of the water heater,
the TP&R connection can leak. The valve must be removed, the threads wrapped
with Teflon tape, and then reinstalled to stop the leak. A faulty TP&R valve
can be another, more serious, cause for a leak. A leaking TP&R valve should
immediately be replaced to prevent a potential explosion.
The drain valve is another primary location on a leaking water heater. Unfortunately,
most manufacturer-installed valves are of poor quality. Consequently, the valve
can be difficult to operate and can leak at the spigot or at the location where
it is connected to the tank. Therefore, we suggest replacing the cheaply manufactured
gate valve with a high-quality brass-ball valve that can be easily operated.
The ball valve will also facilitate the flushing process by improving the volume
of water allowed to exist in the tank during the flushing process. Since a ball
valve is opened and closed with a right angle turn, we suggest that you install
a brass cap on the discharge port of the valve to prevent accidental operation
that can result in burning or a flood.
Be alert to your water heater's needs and it will give you many years of energy-efficient,