Can You Use Dehumidifier with Swamp Cooler? (It's Tricky)

Last Updated on January 1, 2024

Swamp coolers are great appliances for cooling indoors and outdoors. It can sufficiently lower your room temperature with low energy consumption. But the only catch is that it needs low humidity to operate appropriately. Otherwise, it won’t work properly. But if your area has high humidity, can you use dehumidifier with it? Does it help using a dehumidifier with a swamp cooler?

Even though using a dehumidifier with your swamp cooler could improve its cooling ability and reduce humidity, it still may not be a good idea. This is because if the dehumidifier is large enough it will radiate enormous heat energy that would work against the cooling of your swamp cooler.

Dehumidifier is compressor-operated just like air conditioner. It gives off heat during the operation. So, if size of dehumidifier is very large then it will generate immense heat, that will cancel out the effect of cooling by swamp cooler.

Thereby multiple factors have to be taken into account to truly know if this will work. The more the humidity is removed by dehumidifier, the more heat is released by its compressor. So, despite lower humidity in your room, cooling effect of your swamp cooler will be majorly cancelled by dehumidifier operation if this is the case.

Don’t worry if you can’t figure it out. I will elaborate further. This article is all about coupling your swamp cooler with dehumidifier. When this is doable? and when it’s not a good idea?

Contents show

Why Swamp Cooler and Dehumidifier Can Work Together?

Basic Working of Both Appliances

Swamp cooler performs cooling by using the principle of evaporation. The construction and working are way simpler than an air conditioner. Water is contained in a reservoir that is sucked by pump and distributed continuously to cooling pads. A blower fan pushes air through cooling pads with water.

The water carried by air is evaporated during the flow and as a result air is cooled. So, what is delivered forward by blower fan is cool humid air. This is the air that you receive from the front end of your swamp cooler. It is as simple as that.

Dehumidifier on the other hand is essentially an air conditioner working on vapor compression cycle. The difference between an AC and dehumidifier is their primary functions.

Primary function of an air conditioner is cooling but it also performs dehumidification with that as secondary function. The primary role of a dehumidifier is extracting water vapors from atmosphere i.e. dehumidification.

Dehumidifier Can Actually Supplement Swamp Cooler Cooling

The cool air from swamp cooler is great but humidity that it carries is only good if you live in an area with a dry atmosphere. If you live in a region with high humidity like Florida or Louisiana, then it can make your home muggy and uncomfortable. High humidity can also damage your home due to mold and mildew.

This is where dehumidifier can play its role by reducing that humidity to make swamp cooler workable. It will supplement cooling and comfortability in two ways:

1. Swamp Cooler Works Better with Low Humidity

Swamp cooler will cool better when relative humidity is low. The reason is that the evaporation of water is inhibited when humidity in the air is high.

In simple words, the less the humidity in the air the better the evaporation. The more the evaporation the more the air is cooled that is delivered by your swamp cooler.

2. Lower Humidity Increases Comfort and Makes You Feel Cooler

The overall humidity indoors is reduced by dehumidifier operation. Adequately low humidity not only adds to your comfort but actually makes you feel cooler. In fact, at the same temperature, you will feel cooler at lower humidity.

Strange Relation of Relative Humidity and Temperature

The reason you feel cooler when humidity is low is the weird relation of humidity in atmosphere and the cool you feel.

Let me explain.

Your body has natural ability to cool by sweating. When it is hot outside, your skin sweats. Water on your skin evaporates and as a result your body cools.

But when humidity is very high, then water is unable to evaporate due to saturation of air with water vapors. As a result, instead of cooling, you feel warmer in higher humidity (even at a lower temperature).

For example, if ambient temperature is 80 °F, then at 45 percent relative humidity, it will feel like 80 °F. At 60 percent relative humidity, it will feel like 82 °F. At 80 percent relative humidity, it will like 84 °F.

Will Using Both Swamp Cooler and Dehumidifier Work? (Factors)

The primary reason of coupling the operation of both appliances is to use cooling from your swamp cooler and cancel its side effect i.e., humidification. Plus, if you are able to size them right you will be able to get better cooling efficiency from you swamp cooler.

Below are the factors that decide whether running both swamp cooler and dehumidifier will work for you.

1. Humidity

Initially the extent of humidity that you have in your region. The more the humidity, the poor the function of your swamp cooler. This means it will have reduced cooling effectiveness as humidity increases due to reduced evaporation. This also means that with greater humidity you will need a bigger dehumidifier.

2. Size/Power of Dehumidifier

Size of dehumidifier is another major factor. You see, dehumidifier is essentially an air conditioner, in construction and working. It has the same basic foundational components as that of an AC.

Thereby, with the cooling it achieves, in order to remove humidity from air, it expels heat. The greater the size and power of your dehumidifier, the greater will be the amount of heat released by its compressor. If it is sufficiently high, it will undermine the cooling effect of your swamp cooler.

So, If the heat evolved by dehumidifier is close to heat removed by your swamp cooler, the duo is just not going to work. As a result, your swamp cooler will have negligible or no effect. In fact, if dehumidifier size is large enough it will heat the room despite swamp cooler operation. In this scenario net effect will be discomfort with loss of electricity.

3. Working Efficiencies of Your Swamp Cooler and Dehumidifier

The lower the working efficiencies of your swamp cooler and dehumidifier, the more the energy will be wasted as heat. Thereby poor working efficiencies will give you poor compatibility of these appliances with each other.

4. Temperature

Moderately high temperature in your region will require relatively less cooling to be done by your swamp cooler to reach comfortable temperature.

Higher the ambient temperature, from your desired temperature, more cooling is required to be performed. Thereby when temperature is very high with relatively high humidity this arrangement will not work.

How to Get Both to Work Best for You?

Perfect Conditions for Dual Operation: When the humidity is moderately high, meaning not so high compared to ideal relative humidity range (30-50%), power required for dehumidification is low and the heat dehumidifier generates is low in comparison to cooling of swamp cooler, both appliances have good efficiencies and indoor temperature is not so far from ideal value (78°F in summer).

These are not the necessary conditions but rather recommended conditions at which combining the working of swamp cooler and dehumidifier will best work.

Direction and Positioning for Best Operation: By proper positioning and direction you can get the max out of your swamp cooler when dehumidifier runs with it.

The best placement of dehumidifier is behind the swamp cooler in direction of swamp cooler inlet vents. This will allow the driest air in the room to move through wet cooler pads. As I discussed earlier, the drier the air the better as it will allow more evaporation and eventually more cooling.

Wrapping Up…

In short, you can use dehumidifier with swamp cooler to reduce humidity and improve cooling. However, the compatibility of both appliances is dependent on various factors, especially humidity and size of dehumidifier.

If humidity is very high, then swamp cooler will not be able to function properly. Further increasing power of dehumidifier reduces humidity but generates more heat that will cancel the cooling effect of your swamp cooler.