Desa VN18B Safety Information And Installation Manual page 12

INSTALLATION
Continued
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
16,000 and 18,000 Btu/hr - 3/8" or greater
26,000 and 30,000 Btu/hr - 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 equip-
ment 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.
IMPORTANT: Hold the pressure regulator
with wrench when connecting it to gas pip-
ing and/or fittings. Do not over tighten pipe
connection to regulator. The regulator body
could be damaged.
12
Pressure
Regulator
Regulator
Bracket
Heater
Cabinet
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 26.
CHECKING GAS CONNECTIONS
WARNING: Test all gas piping
and connections, internal and
external to unit, for leaks after
installing or servicing. Correct
all leaks at once.
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.
gas, make sure external regula-
tor has been installed between
propane/LP supply and heater.
See guidelines under Connect-
ing to Gas Supply, page 11.
www.desatech.com
3"
Min.
Tee Pipe Cap
Joint Nipple
Sediment Trap
Figure 15 - Gas Connection
WARNING: Never use an
CAUTION: For propane/LP
3/8" NPT
Pipe
Nipple
Ground
Joint
Union
Equipment
Shutoff Valve*
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)
119342-01B