If you dehumidifier doesn't work well, it could be that you did not buy the right size of dehumidifier for the area / space you have. (Check out: How Dehumidifier works and Dehumidifier Buying Guide).

Check and compare the capacity of the dehumidifier and the area of the room. Does the dehumidifier have the capacity to handle the area it is installed in? Capacity of a dehumidifier should always be little than required. If area of the room and capacity of the dehumidifier doesn’t match, maybe you should change it.

In case you don’t want to replace it, close all doors and dehumidify one corner of the room at a time. You can also do following:

1. Unplug the dehumidifier and clean its condenser and evaporator coils. Check if the condenser is clogged with dust or dirt. If yes, clean it.

2. Lubricate the fan motor bearings with oil if the motor has oil ports.

3. Using a volt-meter, check if the humidistat is working properly by testing it with a volt-ohm meter. Refer to the operating manual of the appliance. If you can’t do it yourself, get it checked by a technician.

If your dehumidifier is completely dead and doesn’t work at all, check following:

1. Check the power source and power cord. If the power cord if faulty, replace it.

2. Remove the cover panel and check if there is any ice inside. If yes, allow the ice melt and do not use the unit for some time. Also check the overflow auto cutoff switch.

3. Plug the appliance, switch on and check.

If it still doesn’t work properly or doesn’t work at all, call an appliance repairperson for advice or take the unit into an appliance repair shop.

A dehumidifier normally frost up when room temperature is less than 65 degrees Fahrenheit. Check your room temperature. If it is less than 65 degrees F, don’t use the dehumidifier for some time. Let the room temperature rise up. If your room temperature is not that cold, there could be some problem with air flow / air movement inside the unit. Do following to troubleshoot this problem:

1. Make sure there is enough space around the unit for air movement. Don’t place the unit too close to the wall of the floor.

2. Referring to the operating manual of the appliance, clean the evaporator coils. Remove all dust buildup.

Sometimes, water pools in a hose or the condenser coils of the dehumidifier get dirty. This leaves an odors. This is an easy to solve problem. Do following:

Empty the reservoir tank. Clean the coils and hose. Mob all damp areas and allow the unit to dry. Don’t use it until it is completely dry.

Strange noise in dehumidifiers is mostly caused by loose, vibrating parts inside the unit. Do following:

1. Remove the cover and look for any loose screws or vibrating parts inside. If yes, fix them at the right place. Also check if the rubber compressor mounts. They should be smooth. If they have hardened, they cannot absorb the unit’s movement. Replace them.

2. Check if the fan is loose from somewhere. If yes, tighten it. Also lubricate the motor’s bearings.

If the unit still makes noise, get it checked by an appliance repairperson. Or take the unit to an appliance-repair shop.

Most normal dehumidifiers need to be checked and emptied regularly unless it is designed to drain automatically. Regular maintenance and care can keep overflowing and leaking problems away. If your dehumidifier is overflowing, you can test the overflow prevention switch with a volt-ohm meter (Refer to the operating manual of the appliance).

Testing a Dehumidifier Humidistat or Overflow Cutoff Switch. How to know if the switch is ok or no?t

Using a volt-ohm meter, clip the leads to the terminals on the switch. Depress the bar or trip lever on the switch. The meters needles should show movement and continuity. If the meter’s needle does not show continuity, the switch may be faulty and need replacement.