Do I need a Dehumidifier if I have an Air Conditioner?

Dehumidifier or air conditioner. If your air conditioner can dehumidify your home, do you need both?

Do I need a dehumidifier or air conditioner?

Dehumidifiers can have many benefits around the home, especially if you live in areas of high humidity or, like much of Australia currently, high rainfall is causing moisture build-up within the home. But if you own an air conditioner, that can be as effective at dehumidification of a room as a dehumidifier. Why would you need a dehumidifier? We have asked the Mitsubishi Electric Technical Team for their advice.


Cooling Mode

It is correct, air conditioners can achieve a small amount of dehumidification while operating in cooling mode. They will remove moisture from the room where the room temperature is more than 2°C above the cooling mode set point. That is, if you have set your air conditioner to run at 23°C the room temperature will need to be at least 25°C when you first turn it on. Any difference below 2°C the compressor will back off and not remove moisture. Or technically speaking, the air conditioner’s coil needs to be below the dew point in the air to remove moisture.

When an inverter air conditioner cools the room to the set temperature and the compressor backs off (and in some cases the indoor fan), it is no longer effective at moisture removal.


Heating Mode

When an air conditioner is operating in heating mode, the unit does not provide dehumidification. The air conditioner coil needs to be below the dew point to remove moisture, and this does not occur during heating mode.


Aircon vs dehumidifier

An air conditioner is designed to provide comfortable conditions indoors. Some dehumidification is achievable in cooling mode in some temperature/humidity ranges, but this is by the principle of refrigeration rather than design.

Air conditioners generally do not have published moisture removal rates in their specifications as they are not designed to be dehumidifiers, and there are too many variables to account for, which will affect dehumidification.

A dehumidifier, on the other hand, is designed specifically to remove moisture from the air all year round. Dehumidifiers have a specified dehumidification rate or absorbed humidity rate generally measured in litres over 24 hours for a given temperature and humidity.

If you require dehumidification in all weather conditions year-round, a dehumidifier could be the more appropriate choice. As an added benefit for those wet days, the Mitsubishi Electric MJ-EV38HR-A has an intelligent laundry mode, handy for reducing drying times when you don’t want to use the dryer or quickly drying delicate fabrics.

For more information on the Mitsubishi Electric EV38HR Dehumidifier and its features go to our dehumidifier page.

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