Desa VF-24N-MHD - Manual (Page 13)

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We recommend that you install a sediment trap in
supply line as shown in Figure 12. Locate sediment
trap where it is within reach for cleaning. Install
in piping system between fuel supply and heater.
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.
CAUTION: Avoid damage to
gas control. Hold gas control
with wrench when connecting it
to gas piping and/or fittings.
INsTallaTIoN
Continued
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 12).
IMPORTANT:
Install equipment shutoff valve
in an accessible location. The equipment shutoff
valve is for turning on or shutting off the gas to
the appliance.
Check your building codes for any special re-
quirements 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.
* Purchase the optional CSA design-certified
equipment shutoff valve from your dealer. See
Accessories, page 25.
** Minimum inlet pressure for purpose of input
adjustment.
Figure 12 - Gas Connection
3" Minimum
CSA Design-Certified
Equipment Shutoff Valve
With 1/8" NPT Tap*
Approved
Flexible Gas
Hose (if allowed
by local codes)
Cap Pipe Tee
Nipple Joint
Sediment Trap
Natural Gas
From Gas Meter
(5" W.C.** to 10.5"
W.C. Pressure)
Propane/LP Gas
From External
Regulator
(11" W.C.** to
14" W.C.
Pressure)
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.
WARNING: Never use an open
flame to check for a leak. Apply a
noncorrosive leak detection fluid
to all joints. Bubbles forming show
a leak. Correct all leaks at once.
CAUTION: Make sure exter-
nal regulator has been installed
between propane/LP supply and
heater. See guidelines under Con-
necting to Gas Supply, page 12.
PRESSURE TESTING GAS SUPPLY
PIPING SYSTEM
Test Pressures In Excess Of 1/2 PSIG
(3.5 kPa)
1. Disconnect appliance with its appliance main
gas valve (control valve) and equipment
shutoff valve from gas supply piping system.
Pressures in excess of 1/2 psig will damage
heater regulator.
2. Cap off open end of gas pipe where equipment
shutoff valve was connected.
3. Pressurize supply piping system by either
opening propane/LP supply tank valve for
propane/LP gas or opening main gas valve
located on or near gas meter for natural gas
or using compressed air.
To Gas
Control