Why Dehumidifier Blows Hot Air: Explained

Have you ever wondered why your dehumidifier is blowing hot air instead of cool air? It can be confusing and frustrating, but fear not – there’s a logical explanation for this phenomenon. Read on to understand why dehumidifiers sometimes blow hot air and how it ultimately helps in removing excess moisture from the air in your surroundings.

How Does a Dehumidifier Work?

Before delving into the reasons behind a dehumidifier blowing hot air, let’s first understand how this handy appliance works. A dehumidifier performs the crucial task of reducing the humidity levels in a room or space by extracting moisture from the air. It does so by employing the following mechanism:

  1. The dehumidifier draws warm, moist air from the room through a grille or vents.
  2. The air passes over a refrigerated coil, also known as an evaporator coil, inside the dehumidifier.
  3. The refrigerated coil rapidly cools the air, causing the moisture in the air to condense into water droplets.
  4. The condensed moisture drips into a collection container or flows directly into a drainage system.
  5. The cooled, drier air is reheated by passing it over a warm coil, called a condenser coil, within the dehumidifier.
  6. Finally, the dehumidifier expels this rewarmed air back into the room, but with significantly less moisture content, resulting in reduced humidity levels.

Reasons Behind a Dehumidifier Blowing Hot Air

Now, let’s explore the various reasons why your dehumidifier might blow hot air:

1. Defrosting Cycle:

A dehumidifier often goes into a defrosting cycle to prevent frost buildup on the evaporator coil, particularly when used in low-temperature environments. During this cycle, the cold evaporator coil might temporarily turn off, and the condenser coil, responsible for reheating the air, keeps running. As a result, the dehumidifier blows hot air for a short period until the frost melts away.

2. Compressor Usage:

Dehumidifiers equipped with a compressor have a valve that reverses the refrigeration cycle momentarily as part of their normal operation. This reversal prevents frost accumulation. However, during this cycle, hot air from the surroundings is blown out, causing the dehumidifier to temporarily blow hot air. Rest assured, this is a necessary process to maintain optimal functioning.

3. Dry Mode Feature:

Many dehumidifiers come with a “Dry Mode” feature. In this mode, the dehumidifier focuses solely on removing moisture from the air without actively cooling it down. The dehumidifier’s fan moves the air over the warm condenser coil, thereby blowing hot air. Although it might not provide immediate relief from the heat, this feature is beneficial as it prevents the room temperature from dropping excessively.

4. Dirty Air Filter:

A clogged or dirty air filter can hinder the airflow in your dehumidifier, leading to insufficient cooling of the evaporator coil. As a result, the evaporator coil might get too cold, causing the condenser coil to overheat and blow hot air. Regularly cleaning or replacing the air filter can help maintain the efficiency of your dehumidifier and prevent it from blowing hot air unnecessarily.

5. Mechanical Faults:

In some cases, a dehumidifier blowing hot air could indicate a mechanical fault or malfunction. This can include issues such as a faulty compressor, refrigerant leaks, or a malfunctioning control board. If you have ruled out other causes and your dehumidifier consistently blows hot air, it is advisable to contact a professional technician for further assistance.

Closing Thoughts

While it can be concerning when your dehumidifier blows hot air, it is typically a normal part of its operation and serves the purpose of effectively removing excess moisture from your environment. Understanding the reasons behind this phenomenon can help alleviate any worries and ensure that your dehumidifier continues to work efficiently. Remember to follow the maintenance instructions provided by the manufacturer to keep your dehumidifier in optimal condition and enjoy a comfortable and humidity-controlled living space.