In the home, water heaters are
among the most indispensable appliances. Considering that water heaters can last up to 20
years, the unit currently found in your home may have some miles on it.
When you're shopping for a replacement water heater, there are
four primary criteria besides cost that you should consider:
should select the most energy efficient water heater for reduced energy
use and long term savings. Second, take into account the space the unit
will fill, and third, consider its durability. Lastly, be sure to
examine the different safety features. And while price is always important, remember the true cost will be spread out over the long life of the heater.
Finding the Right Water Heater
You know you should consider energy efficiency, size and
durability and safety when selecting a replacement water heater.
terms of efficiency, you should look for a water heater with a high
first hour rating (FHR). This is a measure of a water heater's
performance from the start. In other words, how much hot water can it
provide starting from an empty tank. It will indicate its reliability
during high-volume use.
Also consider the energy factor of the unit,
which measures efficiency. This number will usually be a fraction such
as .85, but it can be higher.
Durability is not always a given, but
with trusted brands you should expect it.
When you consider size,
size, storage type units are much larger than tankless units which can
Some water heaters, such as heat pump units, need at least
1,000 cubic feet surrounding them while others will function safely in
Above all else, safety is important. A gas water heater
should have a sealed combustion chamber. Direct-vent or power-vented
units help to dissipate excess heat and fumes. Look for units with
safety features built in such as auto overheat protection and a carbon
monoxide sensor for gas units.
Water Heater Options
Replacing a water heater, you have two main options. You can
either go with a conventional storage tank type water heater or opt for
a tankless, demand water heater.
In residential applications, storage
tank type water heaters range in size from 20 to 80 gallons, although
20-gallon units will serve only single-dweller homes.
heaters, just as their name suggests, use no storage tank. Instead,
they heat water instantly as it is demanded. Both types have their
merits and their drawbacks.
The next major choice you have to make is the fuel type. Water
heaters are fueled most commonly by electricity and natural gas, but
liquid propane and fuel oil are used as well. Access to fuel may
determine the type you use. If you do not have a natural gas to your
home, installing one will be initially expensive, so you might opt for
an electrical unit.
Storage Tank Water Heaters
Now that you have an idea of what to look for when replacing a
water heater, it's time to look at the different types available.
If you are considering a storage type unit, you have a
choice between conventional electric resistance, gas combustion, gas
condensing, oil-fired and heat pump water heaters.
Those types with the
highest energy factor (EF) are heat pump units and high efficiency
electric units. Next efficient are gas condensing units, followed by
gas combustion and oil-fired water heaters. Heat pump water heaters
draw in warm air and transfer its warmth to the water, easing the
strain put on the heating elements. This makes them the most efficient,
but they also require adequate space and cannot be installed in cold
The size of storage type water heater you choose should
reflect your home hot water needs. Storage type water heaters can
suffer from standby heat loss; heat energy loss occurring because
heated water is not immediately used. A well-insulated tank and one
that is not too big for your needs can help to mitigate this energy
Tankless Water Heaters
Thanks to their compact, lightweight size, relatively easy
installation and instant hot water-heating ability, tankless water
heaters are becoming more popular. Moreover, tankless units provide an
endless supply of hot water.
The recovery rate of hot water is measured
in terms of gallons per minute (GPM). When a hot water tap is turned
on, cold water moves through the tankless water heater where the gas or
electric heat exchanger immediately heats it and channels it to the
tap. As the demand for hot water increases, the water flow rate reaches
its maximum potential.
Tankless units can serve a whole house, while
smaller varieties make excellent point of use water heaters. For
example, a unit installed under a sink providing hot water just for
that sink. Usually heating water in stages, tankless water heaters have
a minimum flow rate of around .6 and can reach 9.8 GPM or higher
depending on the unit and other conditions.
Tankless water heaters do not suffer from standby heat loss,
for they produce no standing hot water. Gas units that feature a
standing pilot light can, however, waste fuel on the light, so look for
a tankless unit with a direct ignition system. In general, electric
tankless water heaters are more efficient, although with advancements
in technology this is not always the case.
While cost is an important
factor, more important is getting the right water heater for your
home's needs. You can spend well over $1,000 on a new unit,
but you can also spend as little as $250. Since you could live with the heater for many years, tt is vital to select a unit that is the right size for your house and is highly energy efficient for the fuel type available.