American Water Heater PowerVent, Инструкция по использованию и уходу

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Thermal Expansion
Determine if a check valve exists in the
inlet water line. Check with your local water
utility company. 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
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 (see illustration below).
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.
Refer to the illustration below 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.
Water Supply Connections
IMPORTANT: 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 cold
water connections on heater.
Any heat applied to the cold
water supply fittings will
permanently damage the
dip tube and heat traps.
NOTICE: The National
Fuel Gas Code (NFGC)
mandates a manual gas shut-
off valve: See (NFGC) for
complete instructions. Local
codes or plumbing authority
requirements may vary from
the instructions or diagrams
provided and take precedent
over these instructions.
Vacuum Relief Valve
(Not Supplied)
If required, install per local codes
and valve manufacturer’s
instructions.
9
Heat trap
6” minimum
Heat trap
6” minimum
Union
To gas supply
Sediment trap
Cap
Ground joint union
Drain Pan Pipe
to suitable drain.
Drain
valve
Relief valve discharge
line to suitable open
drain.
To cold water
supply
6” Air gap
Blower assembly
1/4” per foot maximum slope up or
down for horizontal venting.
Auxiliary catch pan
Union
Anode
Vent connector
Thermostatic gas valve
Jacket door
Manual gas shut-off
Temperature and
pressure relief valve
Shut-off valve
Shut-off
valve
Thermal expansion
tank (if required)
Combustion Air
Inlet Openings
Hot water outlet to
fixtures
Water Heater Jacket
Flammable Vapor Sensor
Typical Installation