12 • Commercial Electric Water Heater Use and Care Guide
INSTALLATION
BACKGROUND:
Water expands when
heated, and the increased volume
of water must have a place to go, or
thermal expansion will cause large
increases in water pressure (despite
the use of a Pressure Reducing Valve
on the main water supply line).
NOTICE:
The main water supply line
will require the use of backflow
preventers and check valves to restrict
water from reentering the public
water system. Backflow preventers
are often installed in water meters
and may not be readily visible. As
a result, most all plumbing systems
today are now “closed,” and almost
all properties now need a Thermal
Expansion Tank.
A Thermal Expansion Tank is a
practical and inexpensive way to help
avoid damage to the water heater,
washing machine, dishwasher, ice
maker and even toilet valves. If
your toilet occasionally runs for no
apparent reason (usually briefly at
night), that may be due to thermal
expansion increasing the water
pressure temporarily.
Water pipe and tank
leaks
Leaks from plumbing pipes or from
the water heater itself can damage
property and could cause a fire risk.
• Install an automatic leak detection
and shutoff device (available at
local
plumbing supplier). These devices
can detect water leaks and can shut
off the water heater’s water supply
if a leak occurs.
Figure 6 -
A suitable drain pan piped to an
adequate drain can help protect flooring from
leaks and drips.
• Install a suitable drain pan (available
at
local plumbing supplier) under
the water heater (figure 6) to
catch condensation or leaks in the
piping connections or tank. Most
codes require, and we recommend,
installing the water heater in a drain
pan that is piped to an adequate
drain. The drain pan must be at least
two inches wider than the diameter
of the water heater. Install the
drain pan so the water level would
be limited to a maximum depth of
1-3/4” (44 mm).
✓
Water temperature
regulation
Figure 7 -
Thermostatic Mixing Valves can help
prevent scalding.
Install Thermostatic Mixing Valves
(figure 7) to regulate the temperature
of the water (for example, kitchen
sink, bathroom sink, bath, shower).
Consult the valve manufacturer’s
instructions or a qualified person.
WARNING! Even if the water heater
thermostat is set to a relatively low
temperature, hot water can scald.
Install Thermostatic Mixing Valves to
reduce the risk of scalding (see page
4).
BACKGROUND:
A Thermostatic
Mixing Valve mixes hot water
from the water heater with cold
water to more precisely regulate
the temperature of hot water
supplied to fixtures. If you aren’t
sure if your plumbing system is
equipped with properly installed and
adjusted Thermostatic Mixing Valves
contact a qualified person for more
information.
INS
TALLA
TION
