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104414
DESA INTERNATIONAL
UNVENTED NATURAL GAS LOG HEATER
WARNING: Never use an open
flame to check for a leak. Apply a
mixture of liquid soap and water
to all joints. Bubbles forming
show a leak. Correct all leaks at
once.
WARNING: Test all gas pip-
ing and connections for leaks
after installing or servicing. Cor-
rect all leaks at once.
CHECKING GAS
CONNECTIONS
Pressure Testing Gas Supply
Piping System
Test Pressures In Excess Of 1/2 PSIG
1.
Disconnect heater and its individual
manual 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
manual shutoff valve was connected.
3.
Pressurize supply piping system by ei-
ther using compressed air or opening
main gas valve located on or near gas
meter.
4.
Check all joints of gas supply piping
system. Apply mixture of liquid soap
and water to gas joints. Bubbles form-
ing show a leak.
5.
Correct all leaks at once.
6.
Reconnect heater and manual shutoff
valve to gas supply. Check reconnected
fittings for leaks.
INSTALLATION
Continued
Figure 14 - Manual Shutoff Valve
ON
POSITION
OFF
POSITION
Open
Closed
Manual
Shutoff
Valve
Figure 15 - Checking Gas Joints
Gas Meter
Manual
Shutoff Valve
Thermostat Gas Valve or
Control Valve Location
Test Pressures Equal To or Less Than
1/2 PSIG
1.
Close manual shutoff valve (see Fig-
ure 14).
2.
Pressurize supply piping system by ei-
ther using compressed air or opening
main gas valve located on or near gas
meter.
3.
Check all joints from gas meter to
manual shutoff valve (see Figure 15).
Apply mixture of liquid soap and wa-
ter to gas joints. Bubbles forming show
a leak.
4.
Correct all leaks at once.
Pressure Testing Heater Gas
Connections
1.
Open manual shutoff valve (see Fig-
ure 14).
2.
Open main gas valve located on or near
gas meter.
3.
Make sure control knob of heater is in
the OFF position.
4.
Check all joints from manual shutoff
valve to thermostat gas valve (thermo-
stat-controlled models) or control valve
(manually-controlled models) (see Fig-
ure 15). Apply mixture of liquid soap
and water to gas joints. Bubbles form-
ing show a leak.
5.
Correct all leaks at once.
6.
Light heater (see Operating Heater,
pages 14 through 16). Check all other
internal joints for leaks.
7.
Turn off heater (see To Turn Off Gas to
Appliance, page 15 [thermostat-
controlled models] or page 16 [manu-
ally-controlled models]).