Desa VGL18NRA, VGL18PRA, VGL24NRA, VGL24PRA, VGL30NRA, VGL30PRA Gas Heater User Manual


 
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112882-01E 15
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 11.
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.
4. Check all joints of gas supply piping system.
Apply noncorrosive leak detection fluid to gas
joints. Bubbles forming show a leak.
5. Correct all leaks at once.
6. Reconnect heater and equipment shutoff
valve to gas supply. Check reconnected fit
-
tings for leaks.
Test Pressures Equal To or Less Than 1/2
PSIG (3.5 kPa)
1. Close equipment shutoff valve (see Figure 15,
page 16).
2. 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.
WARNING: Use pipe joint
sealant that is resistant to liquid
petroleum (LP) gas.
We recommend that you install a sediment trap in
supply line as shown in Figure 14. 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
regulator. Hold gas regulator
with wrench when connecting it
to gas piping and/or fittings.
* Purchase the optional CSA design-certified
equipment shutoff valve from your dealer. See
Accessories, page 29.
** Minimum inlet pressure for purpose of input
adjustment.
Figure 14 - Gas Connection
INSTALLATION
Continued
Cap Pipe Tee
Nipple Joint
3" Minimum
Sediment Trap
Gas
Control
From
External
Regulator
(11" W.C.**
to 14" W.C.
Pressure)
CSA Design-Certified
Equipment Shutoff Valve
With 1/8" NPT Tap*
Approved Flexible
Gas Hose (if allowed
by local codes)