Quite often we receive complaints about the AC not removing humidity effectively from inside the home. The stuffy and uncomfortable environment becomes unbearable. The constant muggy feeling leaves you annoyed and irritated. If you are worried about the high humidity inside your home, this article is just for you.
How Does AC Get Rid Of Humidity?
To understand the cause of high humidity in your home, you need to first understand how an air conditioner removes moisture from the air. Your AC not only cools the air but at the same time, it also acts as a dehumidifier. Inside the AC is the evaporator coil. When running, the temperature of this coil is below the dew point due to the cold refrigerant inside it. Dew point is the temperature at which moisture leaves the air and condenses. When warm and moisture-laden air comes in contact with the cold evaporator coils, it cools down and also loses moisture to a large extent. So, as the AC functions, it brings down the temperature in your home and also gets rid of the humidity. However, to do so effectively, your AC needs a longer run time.
Causes Of High Humidity
Why is my home so humid with the AC on? We are frequently asked this question. There could be several causes of high humidity, even when the AC is on.
1. Frozen Evaporator Coils – If there is frost on the evaporator coils, it acts as a barrier. Since the air cannot come in direct contact with the cold coils, the cooling and dehumidification of air are compromised. As a result, your home does not cool down sufficiently, and on top of that, it feels humid.
2. Dust & Debris – There is an air filter close to the air handler preventing dust & debris from entering and accumulating on sensitive parts. Nonetheless, some particles still find their way inside. The AC condenser coil in the outdoor unit is particularly susceptible to becoming impaired – the primary reason for this being constant exposure to the elements of nature. When the condenser coil is dirty, it is unable to dissipate heat effectively. In turn, the unit works harder to keep up and disrupts the refrigerant cycle. The overall effect is that your air conditioner heats up, raising the temperature inside the home and fails in drawing out moisture.
3. Oversized AC – You thought bigger the better and landed up purchasing an AC that was too big for your home. Your basic assumption was that it would cool your home faster and so your electricity bill would be low. But your thinking was far off the mark. Yes, an oversized AC will cool your home faster, but it will not remove humidity effectively. An oversized AC has shorter cycles due to which the air retains most of the moisture. To remove humidity, the cycles have to be longer so that more moisture can be drawn out from the air. An oversized AC is a costly mistake, be wry of making it. You can always approach an HVAC company to calculate the size or load of AC that will suitably meet the requirements of your home.
4. Negative Air Pressure – Do you feel a sudden gust of air when a door opens and closes. This is due to negative air pressure inside the home. If the weather outside is very humid, the gust of air that blows inside will bring with it additional moisture and make the room muggier. This problem usually arises due to faulty ductwork. It may also occur because you forgot to upgrade the ductwork when you made changes in your home.
5. Old System – Your HVAC system or AC unit has become old and is unable to remove humidity effectively. There is not much you can do here. Since your unit is old, it would be best to replace it in order to avoid constant repairs.
Other Causes Of Humidity
Above we discussed the most common causes of humidity in the house even when the AC is on. But these are not the only reasons. There could be others as well like –
1. The gutters are blocked, so water is seeping into the walls and causing dampness.
2. There is a broken pipe through which water is leaking into the home, increasing the muggy feeling.
3. Cooking is adding to the moisture levels in the home.
4. Moisture and steam from the shower also find its way into the air.
Though this too is not an exhaustive list, what we are trying to convey is that it is not necessary that the problem is in the AC. It could very well lie elsewhere.
As we saw above, there could be multiple reasons for your house being humid even with the AC on. The solution lies in figuring out the cause of it. Most AC problems, along with that of controlling humidity, can be addressed through seasonal maintenance. This maintenance should be performed by a trained technician only. They have a complete list of jobs to perform and also know the triggers that are indicative of future AC troubles. Overlooking maintenance may save you a few dollars in the present. However, the truth is that it is creating expensive repair problems for the future. You may feel confident that your AC does not need any fiddling, but the fact is that it is a machinery that may need a little tweak to keep it working efficiently.
Food For Thought
You asked, “Why is my house so humid with the AC on”? We gave you a list of possibilities causing that. The real test is in identifying the problem correctly and addressing it immediately. So if your AC is on and yet you feel muggy inside, it’s time to call your local HVAC company. They are the experts who will look at each aspect that could be adding to the humidity. The chances are that there could be more than one. They will look at them all and solve them to your complete satisfaction.