BRACKET, PILOT (W/ORIFICE)
SHIELD, PILOT
SCREWS
BURNER CASTING
ORIFICE, PILOT
THERMOCOUPLE,
21
IN.
TUBING, PILOT W/NUTS
1. Shut off gas supply to appliance inlet.
2. Disconnect heater from electrical supply.
3. Let the heater cool down so pilot assembly is cool to
touch.
4. Remove upper screw on pilot assembly. Loosen
lower screw.
5. Pull up on the pilot shield exposing pilot bracket, pilot
orifice, and thermocouple.
6. Using a soft brush or compressed air, clean pilot
stack of dust and dirt, paying particular attention to
the throat of the pilot stack and the flame spreader
at the top of the stack.
7. Brush off top of pilot orifice making sure dust and
dirt have not plugged orifice hole. If orifice must be
removed, loosen the compression fitting and pilot
tube from the inlet of the pilot orifice. Loosen the
pilot orifice from the pilot bracket. Hold orifice up to
the light to see if the hole in the orifice is clear and
open. If not, blow out with compressed air.
8. To replace shield and pilot orifice, reverse above
procedure.
9. Check for gas leaks.
FIG. 10
PILOT LIGHT ASSEMBLY
1. Shut off gas supply to heater.
2. Disconnect heater from electrical supply.
3. Remove access panel on air inlet end of heater on
case assembly.
4. Remove thermostat cover and disconnect motor
leads from wire nut and thermostat.
5. Remove nuts that secure square motor mounting
plate to “L” bolts on housing.
6. Remove four (4) screws that secure motor mounting
plate to housing.
7. Pull motor, mounting plate and fan assembly from
housing.
8. Loosen set screw(s) on fan wheel with appropriate
wrench.
9. Pull fan wheel from motor shaft. Use wheel puller if
necessary.
10. Remove four (4) nuts securing motor to mounting
plate.
11. To replace, reverse above procedure.
NOTES: 1. Fan wheel to motor mount clearance must be
adjusted to 6.35 MM clearance before
tightening fan wheel to motor shaft.
2. Make sure that set screw(s) of fan are on “flats”
of motor shaft when tightening.
FIG. 9
Service Instructions
MOTOR AND FAN WHEEL ASSEMBLY
MOTOR MOUNT PLATE
FAN WHEEL
CLEARANCE
MOTOR
IMPORTANT
The hole in the pilot orifice is drilled to a specific diameter
to match the fuel and gas pressure being used. Do not
poke or push sharp instruments into the hole. Doing so
will enlarge the hole, creating pilot light outage problems.
Clean the orifice only with the compressed air, soft brush,
or a dry rag. If necessary, replace the pilot orifice.
Do not use a pliers to remove the pilot orifice. A pliers will
“round off” the hex head nut on the base of the orifice,
creating difficulty in servicing at a later time. Only use a
wrench.
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