Desa VyS18NC - Manual (Page 13)

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INSTALLATION
Continued
CONNECTING TO GAS SUPPLY
WARNING: This appliance
requires a 1/2" NPT (National
Pipe Thread) inlet connection to
the pressure regulator.
WARNING: A qualified
service person must connect
heater to gas supply. Follow
all local codes.
CAUTION: Never connect
propane/LP heater directly to the
propane/LP supply. Propane/LP
heaters require an external regu-
lator (not supplied). Install the
external regulator between the
heater and propane/LP supply.
WARNING: For natural gas
units, never connect heater to
private (non-utility) gas wells.
This gas is commonly known
as wellhead gas.
Installation Items Needed
Before installing heater, make sure you have
the items listed below.
• external regulator (supplied by installer)
• piping (check local codes)
• sealant (resistant to propane/LP gas)
• equipment shutoff valve *
• test gauge connection *
• sediment trap
• tee joint
• pipe wrench
* 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.
For propane/LP gas, the installer must supply
an external regulator. An 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 external regulator with vent point-
ing down as shown in Figure 12. Pointing vent
down protects it from freezing rain or sleet.
CAUTION: Use only new, black
iron or steel pipe. Internally-tinned
copper tubing may be used in
certain areas. Check your local
codes. Use pipe of 1/2" diameter or
greater to allow proper gas volume
to heater. If pipe is too small, undue
loss of volume will occur.
Installation must include an 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 13 page 14).
IMPORTANT: Install equipment shutoff valve
in an accessible location. Main gas valve is
for turning on or shutting off gas to the ap-
pliance.
Check your building codes for any special
requirements for locating equipment shutoff
valve to fireplaces.
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.
Figure 12 - External Regulator With Vent
Pointing Down
Propane/LP
Supply Tank
External
Regulator
with Vent
Pointing
Down