Desa LSFG20NT Safety Information And Installation Manual page 10

INSTALLATION
Continued
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 incoming gas pressure,
heater regulator damage could occur. Install the
external regulator with the vent pointing down
as shown in Figure 10. 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
20,000 Btu/Hr Models - 3/8" or greater
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 11).
Propane/LP
Supply Tank
Figure 10 - External Regulator With Vent
Pointing Down
10
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.
Apply pipe joint sealant lightly to male NPT
threads. This will prevent excess sealant from
going into pipe. Sealant in pipe could result in
clogged heater valves. Most flex gas tubing does
not require sealant. Read instructions supplied
with flex gas tubing.
sealant that is resistant to liquid
petroleum (LP) gas.
Flex Gas
Line
3/" Male
Flare
to NPT
Connector
Pipe Joint
Sealant
Required
(NPT End)
Tee Joint
Reducer
Bushing
to 1/"
NPT
1/" NPT
External
Plug Tap
Regulator
Test Gauge
Connection*
Vent
Pointing
Down
* 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 21.
www.desatech.com
WARNING: Use pipe joint
Rear View
3/" Male
Flare to NPT
Connector
Equipment
Shutoff
Valve*
3/" NPT
Pipe Nipple
3" Min
Cap Tee
Joint Nipple
Sediment Trap
Figure 11 - Gas Connection
Hole
Provided
in Rear
Surround
Pipe Joint
Sealant
Required
(NPT End)
Pressure
Regulator
Natural Gas
From Gas Meter
(4" W.C. to 10.5"
W.C. Pressure)
Propane/LP
From External
Regulator
(11" W.C. to 14"
W.C. Pressure)
Pipe
116307-01C