In an effort to reduce energy consumption or save money some folks wonder if they can nix the A/C all together and get away with using just a whole-home dehumidifier. If you are living without air conditioning and the humidity is making you feel uncomfortable or your current air conditioner is not reducing humidity levels enough, it is a valid question. Before you toss out your air conditioner and go all-in with just a dehumidifier, we want to let you in on some essential information first.
The right kind of dehumidifier can effectively work WITH an air conditioner to make your home more comfortable but in most circumstances, it cannot replace an air conditioner. A dehumidifier and an air conditioner both remove humidity from the home, but they differ in how they do the job.
A dehumidifier draws in the damp air and removes the moisture by moving the air through tubes and fins that are kept colder than the dew point of the incoming air. The dew point is the temperature at which moisture in the air will condense from a vapor back to a liquid.
After the moisture is removed the air is then reheated before being sent back into the home. This mean the air returned to the home will be warmer and drier than it was when it was removed.
An air conditioner also draws in the warm humid air from your home, but it removes both the heat and moisture. By moving the air across coils containing refrigerant it cools the air so that the moisture is condensed and drained away and the heat that is absorbed is released through the air conditioner’s outdoor unit. So, the air returned will be cooler and drier than it was when it was when it was removed.
Before you decide which system would work best for your situation let us first discuss what exactly humidity is, how it impacts the comfort level in your home, and how it affects your health.
Then, we will dig into the merits and limitations of using a whole-home dehumidifier versus an air conditioner. In what circumstances you can use a dehumidifier by itself, when you would not need one, and why you might consider both a dehumidifier and air conditioner.
It’s Not the Heat, It’s the Humidity
Have you noticed any small black spots or water stains on your walls and ceilings? Or maybe you have observed condensation on your windows. There could even be an unpleasant musty smell from bathrooms, the basement, or kitchen. If you experience one or more of these signs, you may have a high level of humidity inside your house.
While enduring high heat can make you uncomfortable, it is high heat combined with elevated levels of humidity that can feel truly unbearable. Why so? The Scientific American publication explains that our body has its own process of releasing heat by evaporating moisture through our skin. If there is already too much moisture in the air, like in places with high humidity, sweat will evaporate much slower, if at all. This will leave you feeling sweaty, sticky, and too hot.
More than just feeling unpleasant, high humidity can actually cause serious health problems. A high level of moisture in a living space is a potential breeding ground for molds, mildews, dust mites, and other allergy triggers. Fungus and bacteria live and thrive in damp places. When inhaled, mold and mildew can cause a person with an allergy to suffer from coughing, itchy eyes, and restricted breathing.
Another problem with excessive levels of humidity and mold growth in your home is that food items such as bread and cereals can quickly go bad and become inedible. As mentioned at the outset you may also see evidence in your home furnishings. If left unresolved it can do permanent damage.
Whole House Dehumidifier vs. Air Conditioner
In a showdown between a whole-house dehumidifier and an air conditioner there is no clear winner because it depends on the unique needs of your house, climate, and personal preference.
Science experts from the Asthma and Allergy Foundations of America (AAFA) state that keeping the level of humidity to 50% or less will reduce the potential health risks. During hot weather that 50% humidity level is also the most comfortable. A whole-home dehumidifier can effectively help you reach that desired level of moisture.
However, after removing the moisture from the air by condensing it, the dehumidifier will REHEAT the dry air before it releases it back to your house. Now, why would it do that? It is, in fact, another way to deal with any extra moisture left in the air. That is how a dehumidifier is able to reach the precise humidity level set by you.
Using only a whole-home dehumidifier will do the simple task of lowering the humidity which can make you feel comfortable if you live in areas with cooler temperatures. For example, if you reside in a heavily wooded area, dampness could be a constant concern, but the climate is not very warm.
If that describes the climate you live in, then a whole-house dehumidifier alone could be the right choice for you. A dehumidifier costs less to purchase and operate than an air conditioner. Additionally, there is no outdoor equipment you will need to find space for in your yard.
However, if you live in a place where summer heat can get very intense, yet you also want to solve a humidity problem, a dehumidifier will not be enough. The warm air that it constantly releases, although dry, will do little to alleviate your discomfort from hot weather.
Air Conditioning Delivers a One-Two Punch
The benefit of an air conditioner is that you can get the best of both worlds. An A/C also draws in warm air, removes the heat and moisture, and releases conditioned air back to the home. The biggest difference is an air conditioner is designed to control the temperature in your house but also removes humidity as a by-product of that process.
So, the A/C performs two key functions: lowers the temperature in your home environment and removes the humidity. This means, some of the benefits you hope to get from a whole-house dehumidifier—a comfortable feeling, inhospitable environment for the growth of mold and allergens, getting rid of those damp and musty smells—you also get with the air conditioner, minus the resulting heat most people are desperate to get rid of.
Plus, air conditioning systems can have high efficiency air filters that serve as additional protection from airborne allergens and dust in your living space. While whole-home dehumidifiers have filters, they are for the protection of the equipment.
If you live in an area with hot and humid summers, then a properly sized air conditioner is the best way to get relief from the heat and humidity. In most circumstances you should not need a whole home dehumidifier.
Two Are Better Than One
There is no “I” in team but there is in whole-house dehumidifier AND air conditioning because sometimes they really are better together! In some cases, if you still feel sticky and clammy despite having a well-running air conditioner you may benefit from adding a whole-home dehumidifier. This may be because the air conditioner is oversized for your house. It cools it down to temperature before it can properly dehumidify.
The humidity levels inside your home are also influenced by the location of your residence, how well it is shaded, and ventilated. If you feel those factors are keeping the humidity levels in your home at an uncomfortable level, then a whole-home dehumidifier in addition to your air conditioner is worth considering.
As mentioned previously, faster dehumidification can also result in better indoor air quality. Additionally, a whole-house dehumidifier will quickly and permanently resolve the stale smell and molds in your cold damp basement, kitchen, or bathrooms.
In cooler months like early autumn or in damp weather conditions such as after a downpour of rain, the general temperature is low yet moist. In this case, a dehumidifier can come to your rescue while giving your air conditioner time to rest.
Of course, if you are using both a whole home dehumidifier and an air conditioner you will see a rise in your monthly energy costs. A dehumidifier does use less energy to run than an A/C so with the right balance, it is possible to still be cost-effective while enjoying a more comfortable home.
Using a dehumidifier by itself works best in cooler climates, or if you live in a mostly shaded area yet the humidity level is high. The best solution for the common household is to rely on an air conditioner for both cooling and dehumidifying. A whole home dehumidifier in combination with an air conditioner is only recommended when you find your air conditioner is not reducing humidity levels enough for your needs due to climate, an oversized air conditioner, or health concerns.