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Dehumidifier Problems and Troubleshooting

Dehumidifiers are used to remove excess moisture from the air. Since humidity can cause mold and mildew to grow, many households use a dehumidifier for health reasons. There are several problems which can cause your dehumidifier to stop working. Use the troubleshooting tips below to keep your dehimidifier in top shape.

Choosing correct capacity

Your geographical region and relative humidity — not just the square footage of the room — will affect the unit size you need. A tightly sealed room that restricts entry of damp outside air will require a less powerful dehumidifier. In general, it is best to check manufacturer specifications for the dehumidification capacity of different models, then choose one size larger. If that isn’t completely effective, add another unit. You can always use the second as a backup.

Maintaining your dehumidifier

Dirty coils are the most common cause of dehumidifier problems. Clean the coils regularly to avoid breakdowns. Start by using a narrow brush to remove the accumulated dirt and debris from the front and rear coil surfaces. Use a vertical motion to prevent any damage or distortion of the coils. Compressed air can also be used to blow away the dirt.

Once this is done, spray an evaporator or condenser coil cleaner on the coils. If these are not readily available, you can use a degreaser or spray detergent. Gently pour water over the fins to wash away the dirt loosened by the spray. Be careful not to allow water to contact electrical components or connections.

Is your dehumidifier not working?

There are three common causes of dehumidifiers freezing up and not working.

  1. Blocked coils that restrict airflow.
  2. Low ambient temperature because units don’t work well in cold rooms.
  3. If both of these issues are addressed, then the most likely cause is low refrigerant in the unit.

Refrigerant leaks in the sealed system aren’t uncommon. Repairing this can be expensive: service calls can be around $80, valve replacement is around $10, and refilling the refrigerant may cost about $80 per pound. Most companies charge a one-pound minimum, even if you need less. It may be more economical to buy a new humidifier.

Indicator light is on, but dehumidifier doesn’t start

If your dehumidifier won’t work with the indicator light on, it is usually because of either a bad compressor or a defective humidistat. Since the light comes on, the humidistat is probably working. You can try resetting the overload and capacitor on the side of the compressor. However, the most likely cause of the problem is that the compressor is damaged. If this is the case, repairing it isn’t a cost effective option and buying a new one may be better.

Burned out fan

Before assuming that the fan motor has failed, check to see if it is getting power. If you have a voltmeter, follow the two wires coming out from the back of the motor to where they end. Turn the compressor on to determine if 120 volts is being supplied. If there are more than two wires, follow the one that goes to a capacitor (a silver colored cylinder) and check the power supply there.

If the power supply is there, that means the motor has gone bad. If there is no power supply, it could mean that a relay is defective and will have to be replaced.

Dehumidifier is running, but no water drains into container

The most likely cause for this problem is a dirty condenser which needs to be cleaned. When a condenser is dirty and clogged, it gets warm. This results in a rise in the Freon pressure, which reduces the evaporator’s ability to remove moisture from the air.

To clean the condenser, remove the screws around the panel, first removing the front and back, then the U-shaped side panel. You can now wash the dirt from the condenser coils. Check the condition of the removable filter before reassembling the unit, since a clogged filter can affect airflow.

If there is no improvement, the Freon level may be low. Freon replacement is a repair that should only be done by professionals. Since the cost of such a repair is high, replacing the unit may be a better option.

If none of these steps help, you should ask Experts on JustAnswer for specific information on troubleshooting your dehumidifier problems.

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