|Instant Water Heaters
Unlike conventional hot water heaters, instantaneous water heaters have no tank.
Rather than warming water and holding it
for later use, an instant water heater produces
hot water on demand by quickly super-heating
the water as it flows past the heater. That
means you pay only for the hot water you
use, and you can get as much hot water as
you need when you need it. And by positioning
the unit close to where the water is used,
there is no waiting for hot water to work
its way up through the pipes from the basement.
When considering an instantaneous
heater, look for:
- Type of heater: electric, natural gas, or
propane powered units. Electric units tend
to be smaller and suitable for single faucets;
gas units tend to be larger, up to the size
required for a whole house. For any choice,
check that you have adequate connections.
Large electric units may be particularly
demanding on your house wiring.
- High energy efficiency - electric units can
achieve 98% energy efficiency.
with electric ignition instead
of a pilot
light can cut your use of energy
- Appropriate size - many on demand water heaters
are small and designed to fit right under
the cabinet or on the wall where the faucet
is, whereas whole house water heaters can
be located anywhere. The capacity of on demand
hot water units is measured in gallons per
minute (gpm) of water flow. A bathroom sink
uses about 1/2 a gallon per minute. Kitchen
and laundry sinks use 1 or 2 gpm, while a
shower and bathtub may use up to 3 or 4 gpm.
A whole house instant water heater only needs
to be large enough to handle the likely demand,
that is, one or two large demands for hot
water at the same time, not the unlikely
load of every faucet in the house running
You might consider using an instantaneous
heater in combination with a conventional water heater in a two-stage heating system or if you
have some long runs to a remote laundry or