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118621-01B
12
Tee Pipe Cap
Joint Nipple
Tee Joint
Reducer
Bushing to
1/8" NPT
1/8" NPT
Plug Tap
* A CSA design-certified equipment shutoff
valve with 1/8" NPT tap is an acceptable al-
ternative to test gauge connection. Purchase
the optional CSA design-certified equipment
shutoff valve from your dealer. See
Acces-
sories
, page 30.
Figure 17 - Gas Connection
Pressure
Regulator
T
es
t G
au
ge
C
on
ne
ct
io
n*
Heater
Cabinet
Sediment Trap
3"
Min.
Natural Gas
From Gas
Meter (7" W.C.
to 10.5" W.C.
Pressure)
Propane/LP
From External
Regulator
(11" W.C. to 14"
W.C. Pressure)
Regulator
Bracket
Ground
Joint
Union
3/8" NPT
Pipe
Nipple
Equipment
Shutoff
Valve*
INSTALLATION
Continued
Figure 16 - External Regulator With Vent
Pointing Down
ing gas pressure, heater regulator damage
could occur. Install the external regulator with
the vent pointing down as shown in Figure
16. Pointing the vent down protects it from
freezing rain or sleet.
CAUTION: Use only new,
black iron or steel pipe. Inter
-
nally-tinned copper tubing may
be used in certain areas. Check
your local codes. Use pipe of
large enough diameter to allow
proper gas volume to heater. If
pipe is too small, undue loss of
volume will occur.
Typical Inlet Pipe Diameters
16-18,000 Btu/hr models - 3/8" or greater
26-30,000 Btu/hr models - 1/2" or greater
Installation must include equipment shutoff
valve, union and plugged 1/8" NPT tap. Locate
NPT tap within reach for test gauge hook up.
NPT tap must be upstream from heater (see
Figure 17).
Propane/LP
Supply Tank
External
Regulator
with Vent
Pointing
Down
CONNECTING TO GAS SUPPLY
WARNING: This appliance
requires a 3/8" NPT (National
Pipe Thread) inlet connection to
the pressure regulator.
WARNING: A qualified ser
-
vice person must connect heater
to gas supply. Follow all local
codes.
WARNING: For natural gas,
never connect heater to private
(non-utility) gas wells. This
gas is commonly known as
wellhead gas.
IMPORTANT:
For natural gas, check gas line
pressure before connecting heater to gas line.
Gas line pressure must be no greater than
10.5" of water. If gas line pressure is higher,
heater regulator damage could occur.
CAUTION: For propane/LP
gas, never connect heater di
-
rectly to the propane/LP supply.
This heater requires an external
regulator (not supplied). Install
the external regulator between the
heater and propane/LP supply.
For propane/LP gas, the installer must supply
an external regulator. The external regulator
will reduce incoming gas pressure. You must
reduce incoming gas pressure to between 11"
and 14" of water. If you do not reduce incom-