www.desatech.com
107886-01J
12
IMPORTANT:
Hold the pressure regulator with
wrench when connecting it to gas piping and/or
fittings. Do not over tighten pipe connection to
regulator. The regulator body could be damaged.
CAUTION: Use only new, black
iron or steel pipe. Internally-tinned
copper tubing may be used in cer-
tain 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
VN20BT, VP20BT - 3/8" or greater
VN30BT, VP30BT - 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.
Apply pipe joint sealant lightly to male NPT
threads. This will prevent excess sealant from
going into pipe. Excess sealant in pipe could result
in clogged heater valves.
WARNING: Use pipe joint
sealant that is resistant to liquid
petroleum (LP) gas.
Install sediment trap in supply line as shown in
Figure 15. Locate sediment trap where it is within
reach for cleaning. Locate sediment trap where
trapped matter is not likely to freeze. A sediment
trap traps moisture and contaminants. This keeps
them from going into heater controls. If sediment
trap is not installed or is installed wrong, heater
may not run properly.
Figure 14 - External Regulator With Vent
Pointing Down
External
Regulator
Propane/LP
Supply Tank
Vent
Pointing
Down
INSTALLATION
Continued
* 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.
Figure 15 - Gas Connection
Pressure
Regulator
Tee Joint
Reducer
Bushing
to 1/8"
NPT
1/8" NPT
Plug Tap
Tee Joint
Pipe
Nipple
Cap
3/8" NPT
Pipe Nipple
Heater Cabinet
Sediment
T
rap
Equipment
Shutoff
Valve *
3" Min.
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)
Ground Joint
Union
Note:
Burner
bracket not
shown for clarity
Test Gauge Connection*
CHECKING GAS CONNECTIONS
WARNING: Test all gas piping
and connections for leaks after
installing or servicing. Correct
all leaks at once.
WARNING: Never use an
open flame to check for a leak.
Apply a noncorrosive leak detec-
tion fluid to all joints. Bubbles
forming show a leak. Correct all
leaks at once.
