L.B. White AD100 - Manual (Page 15)

Service Instructions
1. Remove the screws securing the motor mounting plate
to the fan housing. See Fig.12 (AD100 shown.)
2. Pull the fan and motor assembly from the housing.
3. Loosen the square head set screw(s) on the fan wheel
with a wrench.
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 for
b ot h t h e A D 0 6 0 a n d A D 10 0 m u s t b e
a d j u s te d to 1 / 4 i n . c l e a r a n c e b e fo r e
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. 12
FIG. 13
MOTOR MOUNT PLATE
FAN WHEEL
CLEARANCE
MOTOR
MOTOR AND FAN WHEEL ASSEMBLY
1. Close the fuel supply valve to the heater and disconnect
the electrical supply before servicing unless necessary
for your service procedure.
2. Clean the heater’s orifice with compressed air or a soft,
dry rag. Do not use files, drills, broaches, etc. to clean
the orifice hole. Doing so will enlarge the hole, causing
combustion or ignition problems. Replace the orifice if
it cannot be cleaned properly.
3. The high limit switch, fuse, and thermostat can be
tested by disconnecting the leads at the component,
and jumpering the leads together.:
-- Reconnect the electrical supply and open fuel
supply valves.
-- If the heater lights, the component is defective
and must be replaced.
-- Do not leave the jumper on or operate the heater if
the part is defective. Replace the part immediately. --
An alternate method for checking the components
is to perform a continuity check..
4. The air proving switch must not be jumpered. If
jumpered, the ignition control will not allow heater
operation. Test the air proving switch for continuity.
If defective, replace the switch
5. Open the respective case panel for access to burner or
fan related components. Open the control box for
access to the ignition controller, and transformer.
6. Disconnect the appropriate electrical leads when
replacing components.
7. Fo r r e a s s e m b l y, r eve r s e t h e r e s p e c t i ve s e r v i c e
procedure. Ensure gas connections are tightened
securely.
8. Af ter servicing, star t the heater to ensure proper
operation and check for gas leaks.
WARNING
Fire and Explosion Hazard
■
Do not disassemble or attempt to repair any heater
components or gas train components.
■
All component parts must be replaced if defects are
found.
■
Failure to follow this warning will result in fire or
explosions, causing property damage, injury, or
death.
GENERAL
WARNING
Burn Hazard
■
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.
MOUNTING PLATE
SCREWS
14