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INDUSTRIAL / COMMERCIAL ELECTRIC UNIT HEATER 240 SERIES HX24-2235-83-3
REPAIR AND REPLACEMENT INSTRUCTIONS
Maintenance and repair must be performed by qualified personnel only.
A. Replacing the High-Limit or Fan Delay Cutouts:
1. Disconnect the heater electrical power supply.
2. For horizontal discharge heaters, the heater will
need to be disconnected and lowered.
3. For heaters with an optional “Heater On” pilot
light, built on fan switch or built on room
thermostat, mark wiring at control board and
disconnect.
4. Remove any adjustable louvers and the front
cabinet section to expose the fan motor and
heating elements.
5. Remove the fan blade, careful not to bend.
6. The temperature high limit and fan delay are
located on a stepped sheet metal bracket directly
below the back heating element. The fan delay is
the cutout directly against the heating element
fin; the temperature high limit is approximately
5/8” below.
7. Mark and disconnect the appropriate wires.
8. Lower the cutout bracket by removing the side
sheet metal screws.
9. Replace the appropriate cutout.
10. Reattach the sheet metal bracket and wiring.
11. Reinstall & verify the fan blade rotates freely.
12. Reassemble, remount and connect heater.
13. Reconnect any wires disconnected in step 3.
14. Perform steps in section titled “OPERATION” to
verify heater performance.
B. Resetting the Optional Manual Cutout:
1. Disconnect the heater electrical power supply.
2. Determine the reason for the manual reset
thermal cutout actuating and rectify the
situation. See section titled “maintenance”.
3. Reset the manual reset thermal cutout by
pressing on the red button located in the back of
the heater marked “RESET”. It may be necessary
to wait for the cutout to cool.
4. Energize the heater electrical supply circuit.
5. Perform the steps outlined in the section
“OPERATION” to verify heater performance.
6. Check out and report any unusual or
questionable operating characteristics, such as
noise, vibration, etc.
7. If heater operation appears normal, place the
unit into normal operation.
C. Replacing the Fan Motor and Blade:
The fan motor is permanently lubricated and does not
require any maintenance. If the fan motor is
defective, a replacement must be obtained from the
factory.
1. Disconnect the electrical power supply.
2. For horizontal discharge heaters, the heater will
need to be disconnected and lowered.
3. For heaters with an optional “Heater On” pilot
light, built on fan switch or built on room
thermostat, mark wiring at control board and
disconnect.
4. Remove any louvers and the front cabinet
section to expose the motor and blade.
5. Remove the fan blade, careful not to bend. If
motor is not being replaced, skip to step 11.
6. Disconnect the motor supply wires, noting their
location.
7. Remove motor mounting screws and lift motor
out of heater assembly.
8. Install new motor to heater using existing motor
mounting hardware.
9. Feed motor wires through snap bushing and into
wiring compartment.
10. Reconnect motor wires.
11. Reinstall & verify the fan blade rotates freely.
12. Reassemble, remount and connect heater.
13. Reconnect any wires disconnected in step 3.
14. Perform steps in section titled OPERATION to
verify heater performance.