15
1. Open the motor end access panel, and disconnect
the motor leads.
2. Remove the motor mounting plate screws and pull
the fan and motor assembly from the housing.
3. Loosen the square head set screw(s) on the fan
wheel.
4. Pull the fan wheel from the motor shaft. Use a wheel
puller if necessary.
5. Remove the four (4) nuts securing the motor to the
mounting plate.
NOTES: a. Fan wheel to motor mount plate spacing
must be adjusted to the clearance
specified in the table below before
tightening the fan wheel to the motor
shaft.
b. Make sure that set screw(s) of the fan are
on the flats of motor shaft when
tightening.

FIG. 8

MOTOR AND FAN WHEEL ASSEMBLY

MOTOR MOUNT PLATE FAN WHEEL
CLEARANCE
MOTOR
NUTS (4)
NUTS (2)
SWITCH
SCREW (2)
FAN HOUSING PANEL
1. Open the motor end access panel and disconnect the
air-proving switch leads.
2. Remove the air proving switch mounting nuts and pull
the switch from the fan housing panel.
3. The replacement switch includes appropriate quantity
of mounting screws and nuts. Slide the switch onto
the screws and secure into place with the two nuts.
4. Reconnect the heater to its electrical supply and open
the fuel supply valves to the heater.
5. Close and latch the access panel. Start the heater
and check for proper operation.

FIG. 9

AIR PROVING SWITCH

Service Instructions
1. Close the fuel supply valve to the heater and
disconnect the heater’s electrical supply before
servicing unless it is necessary to have the valve
open and electrical supply connected for your service
procedure.
2. For reassembly, reverse the respective service
procedure. Ensure gas connections are tightened
securely.
3. After servicing, start the heater to ensure proper
operation and check for gas leaks.
4. Clean tthe hheater’s bburner oorifice wwith ccompressed aair
or aa ssoft, ddry rrag. DDo nnot uuse ffiles, ddrills, eetc. tto cclean
the oorif ice hhole. DDoing sso mmay een large tthe hhol e,
causing ccombu stion oor iignition pproble ms. RReplac e
the oorifice iif iit ccannot bbe ccleaned pproperly.
WARNING
BBuurrnn HHaazzaarrdd
■Heater surfaces are hot for a period of time after the
heater has been shut down.
■Allow the heater to cool before performing service,
maintenance, or cleaning.
■Failure to follow this warning will result in burns
causing injury.

GENERAL

WARNING
FFiirree aanndd EExxpplloossiioonn HHaazzaarrdd
■Do not disassemble or attempt to repair any
component part of the heater, including regulators
and gas hoses.
■All components must be replaced if defects are found.
■Failure to follow this warning will result in gas leaks.
■Gas leaks cause fire or explosions, leading to property
damage, injury, or death.
1/8 IN.