Mr. Heater MH75KTR User Manual (English)

Questions and Answers:

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Anthony WestAug 17, 2025
What to do if my Mr. Heater Heater has no spark?
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  Michael TorresAug 17, 2025
  If your Mr. Heater Heater is not sparking, verify the extension cord's length and gauge to ensure it provides the correct amperage. Check the wiring to the igniter using the wiring schematic. Ensure the gap between the electrode probes is within the range of 2.3 to 3 mm. If there is still no spark, replace the igniter assembly. As a last resort, consider replacing the oil flame control assembly.
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Timothy FordAug 21, 2025
What to do if my Mr. Heater Heater is unable to detect flame?
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  jhamiltonAug 21, 2025
  If your Mr. Heater Heater is unable to detect a flame, begin by checking the wiring to the cad cell, referring to the wiring schematic. Next, clean the cad cell photo cell. If the heater still fails to operate, replace the cad cell. If the issue persists, consider replacing the oil flame control assembly.
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Sharon MurphyAug 28, 2025
What to do if my Mr. Heater Heater has abnormal motor operation?
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  Joseph AustinAug 29, 2025
  If your Mr. Heater Heater's motor is overheating or stopping, it could be due to several reasons. The motor speed might be too low (it should operate at 3450rpm), in which case, replace the motor. With the heater disconnected from the power source, try rotating the fan clockwise to check if the motor is free. Also, remove the air filter housing and inspect the pump rotor for damage, replacing the rotor assembly if needed. If the wiring is correct and the pump rotor is okay, but the motor still isn't rotating freely, you may need to replace the motor or power-pack assembly. If the problem persists, consider replacing the oil flame control assembly.
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Veronica ThomasSep 1, 2025
What to do if my Mr. Heater Heater has a CAD cell failure?
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  Katherine RobertsSep 1, 2025
  If your Mr. Heater Heater is experiencing CAD cell failure, first check the wiring to the cad cell using the wiring schematic. Then, clean the cad cell photo cell. If the heater still doesn't operate after these steps, replace the cad cell. As a final measure, consider replacing the oil flame control assembly.
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andrewsteeleSep 5, 2025
What to do if my Mr. Heater Heater has a high limit switch failure?
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  Kristin StewartSep 5, 2025
  If your Mr. Heater Heater is experiencing a high limit switch failure, ensure the heater has cooled down, then press the reset switch and try again.
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Michael DrakeSep 9, 2025
What to do if my Mr. Heater Heater has a high limit switch open circuit?
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  Catherine LewisSep 9, 2025
  If your Mr. Heater Heater has a high limit switch open circuit, ensure that the heater is cooled off, toggle the switch to the “OFF” position, wait 5 minutes, and then try again.