Models > MDDQ40FW1

MDDQ40FW1 Frigidaire Dehumidifier - Overview

Get Parts and Repair Help for MDDQ40FW1

If you know the dehumidifier repair part you need, you can browse the list of all parts on the MDDQ40FW1, or you can search by name or part description. You can also find your part by where it is located on the MDDQ40FW1 by selecting a section below. Installation instructions provided by other do-it-yourselfers will help guide you through your repair.


Compressor Start Relay




Humidistat Control

This control needs to be replaced if the dehumidifier won't shut off.


Auto Shut Off Switch

Water Container Reservoir and Float






Defrost Thermostat

The thermostat senses that the heat near the cooling coils has reached the desired temperature.





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Compressor was short cycling

  • Customer: Sherman from Tuttle OK
  • Difficulty: Easy
  • Time to Complete: 30 - 60 mins
  • Tools Required: Screw drivers
  • 5 of 9 people found this instruction helpful
Removed the cowling with a square drive screw driver, removed the spring clip from the cover of the compressor controls with a screw driver, pulled off the old compressor start relay and replaced it with the new part. Since other problems could have caused the compressor to short cycle this was a "replace the part and hope it would work" since that would be ... read more

Unit would run continuously and not shut off

  • Customer: Jonathan from New Oxford PA
  • Difficulty: Really easy
  • Time to Complete: Less than 15 mins
  • Tools Required: Screw drivers
  • 3 of 4 people found this instruction helpful
Removed the front cover and then the humidistat from the bracket. Two push on wire connectors and then reversed. Very straightforward and excellent part matching. Given the prices for new dehumidifiers it was great to breathe life back into this unit which does its job well. Thanks for the easy to use web site and fast fast service! read more

Humidistat was inoperatative and the defrost thermostat.

  • Customer: Martin from Lords Valley PA
  • Difficulty: Really easy
  • Time to Complete: Less than 15 mins
  • Tools Required: Screw drivers
  • 7 of 16 people found this instruction helpful
Removed two screws holding the faceplate that held the humidistat. Removed knob, and two screws holding humidisat.. Removed two wires (push on terminals) . Reversed procedure to install new humididstat. Removed defrost thermostat from suction line, cut wires, installed new defrost thermostat, stripped wires, used wire nuts to connect control. Replaced facepl... read more