Desa GMP26 Water Heater User Manual


 
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12
INSTALLATION
Continued
Figure 14 - External Regulator With Vent
Pointing Down
External Regulator
Propane/LP
Supply Tank
Vent
Pointing
Down
Tee Joint
Reducer
Bushing to
1/8" NPT
1/8" NPT
Plug Tap
Test Gauge Connection*
3/8" NPT
Pipe Nipple
Heater
Cabinet
Equipment
Shutoff
Valve *
3" Min.
From External
Regulator
(11" W.C. to
14" W.C.
Pressure)
Ground Joint
Union
Tee Joint
Pipe
Nipple
Cap
Sediment Trap
Figure 15 - Gas Connection
Pressure
Regulator
* A CSA design-certified equipment shutoff valve
with 1/8" NPT tap is an acceptable alternative to
test gauge connection. Purchase the optional CSA
design-certified equipment shutoff valve from your
dealer. See Accessories, page 25.
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.
CAUTION: Never connect
heater directly to the propane/
LP supply. This heater requires
an external regulator (not sup-
plied). Install the external regu-
lator between the heater and pro-
pane/LP supply.
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 inches of water. If you do
not reduce incoming gas pressure, heater regula-
tor damage could occur. Install the external regu-
lator with the vent pointing down as shown in Fig-
ure 14. 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
GMP20PT, GMP16(T) - 3/8" or greater
GMP30BT, GMP26(T) - 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 15).
IMPORTANT:
Install an equipment shutoff valve
in an accessible location. The equipment shutoff
valve is for turning on or shutting off the gas to
the appliance.