Dehumidifier: Why does my dehumidifier run all the time?
If the dehumidifier runs continually and constantly collects water, it's likely that the dehumidifier's capacity is too low for the space; add another dehumidifier to the space to increase the water-collection capacity.
A defective humidity sensor can also cause the dehumidifier to run constantly. If the evaporator is iced up and not defrosting, you may need to replace the dehumidifier defrost sensor-, because the unit won't collect water if the evaporator is iced up.
If you see no frost on the evaporator while the dehumidifier is running, and the dehumidifier isn't collecting water, the dehumidifier may be low on refrigerant or the compressor may be defective. See the repairs below for ways to correct the problem.
THESE REPAIRS MAY HELP SOLVE YOUR DEHUMIDIFIER PROBLEM
Replace the dehumidifier evaporator thermistor
The evaporator thermistor is a temperature sensor on the evaporator coils. It communicates the temperature of the evaporator coil to the electronic control board; if the temperature is too low, the electronic control board detects excessive frost and begins the defrost cycle. If the thermistor isn't working properly, the electronic control won't defrost the coils. Replace the evaporator thermistor if it doesn't detect the evaporator temperature.
Dehumidifier evaporator thermistor
How to replace a dehumidifier sensor assembly
If your dehumidifier's bucket isn't filling with water, the sensor assembly might be the problem. This DIY repair guide has clear, step-by-step instructions that explain how to replace a dehumidifier sensor assembly.
Replace the dehumidifier humidistat
The humidistat is a sensor on the front of the evaporator coil that monitors the humidity of the room air being pulled in through the evaporator. The humidistat communicates the humidity to the electronic control board through a wire harness connection. If the thermistor is defective, the electronic control won't properly detect humidity and dehumidify the room. Replace the humidistat if it doesn't sense the humidity.
Dehumidifier humidistat
How to replace a dehumidifier sensor assembly
If your dehumidifier's bucket isn't filling with water, the sensor assembly might be the problem. This DIY repair guide has clear, step-by-step instructions that explain how to replace a dehumidifier sensor assembly.
Symptoms common to all dehumidifiers
Choose a symptom to see related dehumidifier repairs.
Main causes: dehumidifier too small for the space, bad humidity sensor, faulty evaporator thermistor, low refrigerant, b…
Main causes: clogged drain hose, drain hose not properly connected…
Main causes: loose fan motor mounting screws, loose compressor mounting bracket screws, bad fan, faulty compressor…
Main causes: collection bucket not installed correctly, cracked collection bucket, loose drain hose connection…
Main causes: lack of electrical power, wiring failure, electronic control board failure, user interface control failure…
Main causes: collection bucket not installed, collection bucket full of water…
Main causes: room temperature below 65 degrees Fahrenheit, control system failure…
Main causes: weak or dead batteries, out of range, radio frequency interference…
Main causes: dirty air filter, clogged grill, dehumidifier placed too close to the wall, dehumidifier too small for the …
Repair guides common to all dehumidifiers
These step-by-step repair guides will help you safely fix what’s broken on your dehumidifier.
How to replace a dehumidifier sensor assembly
If the humidifier sensor doesn’t properly detect humidity or evaporator temperature, install a new sensor assembly, foll…
How to replace a dehumidifier user interface control board
If the dehumidifier doesn’t respond when you try to set it, follow these steps to replace it.…
How to replace a dehumidifier electronic control board
If the dehumidifier won’t power up because the control board has failed, use the steps in this repair guide to replace t…
Articles and videos common to all dehumidifiers
Use the advice and tips in these articles to get the most out of your dehumidifier.
Learn some of the most common symbols found in a wiring diagram and what they mean.…
Learn how to repair broken, frayed or damaged wires in your appliances.…
Learn how to use a multimeter to check for wiring problems in an appliance that's not working…