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SERVICE
PROCEDURES
WARNING
Turn off and unplug heater and let cool before servicing.
Unless you need gas supply for testing, shut off manual
shutoff valve before servicing. Only a qualified service per-
son should service and repair heater and venting system.
Removing Control Valve
and Burner Tube
1. Shut off gas supply to
heater.
2. Remove lower front
access panel on heater.
3. Disconnect burner tube
from orifice holder (see
Figure 18).
4. Remove pilot gas line
from control valve (see
Figure 18).
5. Disconnect wire connec-
tors from thermocouple
interrupter (see Figure
18).
6. Remove thermocouple
and thermocouple inter-
rupter from control valve.
7. Remove cotter pin from
control valve. This
releases the control rod
from valve (see Figure
18).
8. Remove the two mounting
screws from control valve
mounting bracket (see
Figure 18).
9. Remove assembly from
the rear of heater. Pull
burner tube through hole
in combustion chamber.
10. To reinstall, reverse above
steps. Turn on gas to
heater and check for gas
leaks. Apply a mixture of
liquid soap and water to
all joints. Bubbles forming
show a leak. Correct all
leaks at once.
11. Replace lower front
access panel.
Figure 18 - Removing Control Valve and Burner Tube
Control Rod
Cotter Pin
Mounting
Screw
Wire Connector
Control Valve
Bracket
Control Valve
Pilot Gas Line
Wire Connector
Thermocouple
Thermocouple
Interrupter
Orifice
Holder
Burner
Tube