Does a Dehumidifier Cool a Room? The Truth Behind Heat vs. Humidity

When your house gets too hot for comfort, it becomes the last place you’d want to be in. It’s uncomfortable to say the least, plus it can lead to serious health problems like dehydration and heat stroke. Fortunately, air conditioners exist to counter heat and make your house as cold as you like. But did you know that dehumidifiers can also have a cooling effect on your home? 

There’s a lot to unpack about this topic. Does a dehumidifier cool a room? Is it enough to replace an air conditioner (and potentially save money on cooling costs)? We answer these questions and more in this blog. 

 

Does a Dehumidifier Cool a Room or Heat It? 

This is a question people who’re discovering dehumidifiers for the first time often ask. Does a dehumidifier make a room cooler? The short answer is no, they don’t cool air the way air conditioners do. However, they can influence your sensory perception and make your house feel cooler even if the temperature stays the same.

We will go into detail about this in the next section. For now, let’s discuss how dehumidifiers are just like any electrical appliance and generate residual heat.

Appliances that convert electricity into various forms of energy produce heat that becomes unutilized and dissipates.

A light bulb is an example of this. It utilizes electricity to produce light, and in the process, the bulb grows hotter the longer it stays on.

The same thing happens with televisions, desktop computers, and gaming consoles that become increasingly hot to the touch. Heat builds when electricity meets resistance from non-conductive materials, like the rubber covering the copper strands of a power cord.

This wasted heat energy from non-heating appliances is usually minimal. However, when you use multiple appliances that generate lots of heat at the same time, you'll notice the room grow warmer.

Dehumidifiers also produce latent heat, which is energy released when a substance transforms from one phase to another. Water vapor turning into liquid through condensation, changing from gas to liquid, is a perfect example. Latent heat is also minimal. You wouldn’t feel it, especially if the dehumidifier is the lone appliance in the area.

Latent and residual heat from electrical appliances shouldn't be that big a problem unless you’re after an actual drop in temperature. In this case, the best thing to do is turn on the air conditioner.

So, can a dehumidifier cool a room? Technically, no. However, it can make you feel cooler and more comfortable even without a significant drop in temperature. This is why you’ll find many resources online saying dehumidifiers aid air conditioners in cooling houses during summer.

 

Drying vs. Cooling

Now, let’s answer this popular question: How does a dehumidifier cool a room? It has to do with perception and comfort. To explain this, we must discuss drying versus cooling.

Drying with a Dehumidifier

Dehumidifiers expedite drying because they remove excess moisture in the air. As mentioned above, water vapor condenses as humid air passes through cooling coils inside a dehumidifier. The condensate drips down to a collection tank or drains through a tube. Depending on the drainage system, the condensate may flow downwards with gravity or drained by a pump.

When a dehumidifier runs, it effectively lowers the room’s relative humidity (RH). Relative humidity is the measure of moisture in the air relative to its current temperature. It can change depending on how cool or warm the air temperature is. The rule of thumb that is the warmer the air, the higher its capacity to hold water.

Cooling with an Air Conditioner

Cooling is the reduction of a room's temperature, usually by using air conditioners. An AC draws in warm air and pushes it through cooling coils filled with refrigerant.

You’ll notice that this process is like how dehumidifiers work. This is because ACs can remove some moisture while cooling the air. This is why you might find online sources saying there’s a dehumidifier in air conditioner units.

However, bear in mind that this is not the primary purpose of an AC. Once the air reaches the desired temperature, the AC will release it regardless of how much moisture it carries. Therefore, depending on an AC for drying a room won’t work because it is only a secondary function. Dehumidifiers are still the most efficient appliances for removing moisture and lowering the RH of a room.

But why is it important to keep RH low?

 

Humidity and Heat Perception

A low RH level is vital for indoor comfort because it allows moisture inside a room to evaporate. The EPA recommends keeping it between 30-50%.

Indoor moisture can come from the humid outdoor air that enters through a window. It can also be from a leaky faucet. When there's too much moisture in the air, the RH percentage will be high.

Here’s something you need to know: when a room has a high humidity level. When it nears or reaches saturation (100% RH), it means the air has maxed out its capacity to hold water. It cannot accommodate any more water vapor, so any remaining liquid in the room can no longer evaporate.

This means if there's condensation on the walls or a damp spot on the carpet, the moisture will stay there. Over time, the humidity will make the room smell and the air feel stuffy. The sweat on your skin? It will make you feel sticky, uncomfortable, and more sensitive to heat.

Now, this is what happens when the RH is low: there’s more room for air to accommodate water vapor. Liquid can finally evaporate, including your sweat. This fulfills the body’s natural cooling mechanism. Therefore, lowering indoor RH not only makes you comfortable but also tempers the way your body perceives heat.  

So, will a dehumidifier help with heat at home? Yes. It lowers a room's RH level, allowing sweat to evaporate and cool the body naturally. This heightens the perception of a room being cool even if the temperature stays the same.

 

Can a Dehumidifier Reduce Cooling Costs?

Yes, it is possible to save on cooling costs when you have a dehumidifier. When you feel comfortable and your skin doesn't feel sticky, there’s less urgency to turn on the AC unit. You might think you can endure the warmth because the air feels light against your skin. Of course, if you use the AC less often or need it only for short hours, you’re using less electricity for cooling.  

But the cost savings don’t stop there.

Drier air makes a house less conducive to mold and slows material degradation. Mold spores need moisture to take root and form fuzzy colonies on walls, ceilings, and behind the drywall. Material degradation or rot, meanwhile, occurs quickly when water penetrates wood and other structural components. 

By letting dehumidifiers remove moisture in your house, you won’t ever have to spend money on mold removal or cosmetic and structural repairs. Yes, an AC may be able to remove some humidity, but for houses in hot and humid regions, a dehumidifier can do the bulk of the work better and faster.

 

When To Use a Dehumidifier vs. Air Conditioner

To round out this discussion on the cooling effect of indoor dehumidification, let’s identify situations that call for a dehumidifier versus an air conditioner. 

As the table shows, the air conditioner is your best option if you wish to keep your house cool throughout the day. You'll also need it if you have heat-generating appliances or electronics that run all day. 

Suppose you work at home and use a desktop computer with three screens for nine hours a day on weekdays. You'll need an AC to protect your computer equipment and ensure your workroom stays comfortably cool.

Is your house humid even with the AC on? Do you have a room that stays damp most of the year? If the answer is yes, then you'll need a dehumidifier. It will keep rooms like this dry and mold-free. It will also make a room feel cooler because, as discussed above, the RH levels will stay low and regulated.

Dehumidifiers and air conditioners operate independently, but you can get the best outcomes if you use them in tandem. There's no need to choose between cooling and drying because you can enjoy what each appliance offers at the same time. 

 

Keep Your Home Cool and Dry with Argendon

Don’t discount the fact that dehumidifiers cannot slash degrees in a thermometer the way an air conditioner does. When it comes to cooling, it’s not a question of can a dehumidifier cool a room. Rather, will it make you comfortable and cool enough that you won’t feel the need to turn on the AC. And the answer is a resounding yes.

Argendon offers several options for dehumidifiers that can do wonders for your home. Choose from compact units perfect for unfinished crawl spaces to portable, standing units that won’t look out of place in your living room. Argendon products will make your home comfortable and bearable even during warm days.

Shop for a dehumidifier today.