Water Connections; Condensate Drain - Rheem HB Series Use & Care Manual

Installing the water heater
6
Thermal Expansion
Determine if a check valve exists in the
inlet water line. Check with your local
water utility. It may have been installed in
the cold water line as a separate back flow
preventer, or it may be part of a pressure
reducing valve, water meter or water
softener. A check valve located in the cold
water inlet line can cause what is referred
to as a "closed water system". A cold
water inlet line with no check valve or back
flow prevention device is referred to as an
"open" water system.
As water is heated, it expands in volume
and creates an increase in the pressure
within the water system. This action is
referred to as "thermal expansion". In
an "open" water system, expanding water
which exceeds the capacity of the water
heater flows back into the city main where
the pressure is easily dissipated.
A "closed water system", however,
prevents the expanding water from
flowing back into the main supply line,
and the result of "thermal expansion"
can create a rapid and dangerous pressure
increase in the water heater and system
piping. This rapid pressure increase can
Water Supply Connections
Refer to the illustration on the next
page for suggested typical installation. The
installation of unions or flexible copper
connectors is recommended on the hot
and cold water connections so that the
water heater may be easily disconnected
for servicing if necessary. The HOT and
COLD water connections are clearly
marked and are 3/4" NPT on all models.
Install a shut-off valve in the cold water
line near the water heater.
Condensate Drains for the Heat Pump
Consult local codes or ordinances for
specific requirements. Refer to page 7.
IMPORTANT: When making drain fitting
connections to the drain tubing, use a thin
layer of piping tape or silicone and install
hand tight.
IMPORTANT: When making drain fitting
connections to the drain tubing, DO NOT
overtighten. Overtightening fittings can
split pipe connections on the drain pan.
• This unit is equipped with a 3/4"
primary condensate connection and a
1/2" overflow connection.
• DO NOT reduce drain line size less
quickly reach the safety setting of the
relief valve, causing it to operate during
each heating cycle. Thermal expansion,
and the resulting rapid and repeated
expansion and contraction of components
in the water heater and piping system can
cause premature failure of the relief valve,
and possibly the heater itself. Replacing
the relief valve WILL NOT correct the
problem!
The suggested method of controlling
thermal expansion is to install an expansion
tank in the cold water line between the
water heater and the check valve (refer
to the illustration on the next page). The
expansion tank is designed with an air
cushion built in that compresses as the
system pressure increases, thereby relieving
the over pressure condition and eliminating
the repeated operation of the relief valve.
Other methods of controlling thermal
expansion are also available. Contact
your installing contractor, water supplier
or plumbing inspector for additional
information regarding this subject.
See page 8 on "To Fill The Water
Heater".
NOTICE: DO NOT apply heat to the
HOT or COLD water connections.
If sweat connections are used, sweat
tubing to adapter before fitting adapter
to the water connections on heater. Any
heat applied to the water supply fittings
will permanently damage the dip tube
traps.
and/or heat
than connection size provided on

condensate drain.

• All drain lines must be pitched
downward away from the unit a
minimum of 1/8" per foot of line to
ensure proper drainage.
• Do not connect condensate drain line
to a closed or open sewer pipe. DO
NOT allow condensate to drain into
the water heater drain pan.
• The drain line should be insulated
where necessary to prevent sweating
and damage due to condensate
forming on the outside surface of the
line.