Updated September 2023
Few things are worse than being stuck in a hot, humid environment. Conditions like these can be downright oppressive. But what about when your San Antonio, Texas home feels cool and clammy? You don’t need heat to have an unpleasant and overly moist living environment. Fortunately, at times like these, you can rely on your air conditioner. Although your AC unit is largely meant for keeping your home cool, it can help on cold, wet days too. Read on to find out about your air conditioner’s dry mode setting, including why and when you should use it.
What Is Dry Mode?
Life is filled with lots of buttons and settings that we never use. However, dry mode is an effective setting that’s found on some central air conditioners and most ductless mini-split AC systems. When you turn your air conditioner to dry mode, it will extract excess moisture from your indoor air, but it won’t provide cooling.
When air conditioners are set to function in standard cooling mode, they provide cooled air, humidity regulation, and a modest amount of air filtration. On hot, muggy days, these three functions contribute to a cleaner, cooler, and all-around more comfortable environment. However, when the indoor air is already cool, you don’t actually need to have cold, conditioned air circulated throughout the building. With dry mode, you can bypass the extra energy use and the added costs of air conditioning by solely using your AC for dehumidification.
How Dry Mode Works
When air conditioners produce cold air, they do so by drawing in warm indoor air. This air gets passed over evaporator coils, which contain refrigerant. As heat is extracted from this air, moisture condenses and forms droplets that are transported away by the air conditioner’s condensate line. This moisture is routed down into the AC system’s drain or drain pan. The resulting air is both drier and colder. It is distributed throughout the home via wall-mounted air registers or central HVAC air vents.
The way an air conditioner functions while in dry mode looks very much the same. The primary difference is that the air moving through the AC isn’t having any heat extracted from it. It’s only having its excess moisture removed. Although the air flowing out of the air vents or air registers during dry mode is cool, it’s only as cool as it was before being pushed through the AC system.
Without dry mode, homeowners who want the humidity regulation that their AC systems normally provide would have to set their thermostats lower than normal on cool, humid days. Dry mode eliminates the need to do so.
Dry Mode and Dehumidification Equipment
AC systems in dry mode sound a lot like dehumidification equipment. In reality, however, homes that need dehumidifiers will still need them even when dry mode is available. Dry mode does not increase an air conditioner’s dehumidification abilities. Whether your air conditioner is set to standard cooling mode or dry mode, it will only have the ability to provide a moderate amount of humidity regulation. If you have consistent problems with excess humidity in your home, you probably need a whole-house dehumidifier instead.
Whole-house dehumidifiers tend to be necessary in homes that house lots of people. They also work well in naturally humid regions. However, excessive indoor humidity can sometimes be the result of fixable issues. For instance, if you have a slow, hidden leak in your home, such as a leaky pipe behind your drywall or a small leak at the back of an appliance, it could be making your indoor air more moist than normal. In this case, scheduling a whole-house plumbing inspection and having these problems found and resolved would be better than investing in dehumidification equipment.
When’s the Right Time to Turn Dry Mode On?
There’s never a bad time to turn dry mode on. If it’s cool in your home, but your skin feels moist and clammy, there’s likely too much moisture in the air. You might want to run your AC in dry mode at certain times.
- Hot shower or bath
- Cooking
- Extra company in the home
- Dryer use
- Rainy, wet days
It is often good to use dry mode on days that are cold and humid outdoors. If humidity is high outside, your home will also be humid within. Many people use dry mode right before or during big rainstorms. Outdoor air can be especially humid during warm spring rains. This is true in the summer and early fall as well.
Things to Remember When Using Dry Mode
There are a few important things to remember when using dry mode to lower humidity in your home. The first is that, unlike the standard cooling mode on your air conditioner, this mode is not governed by your thermostat’s temperature reading. Dry mode will stop running when your indoor temperature drops to a certain level. For most air conditioners, this setting has to be manually turned on and off.
It is possible to leave an air conditioner running in dry mode for too long. Most HVAC manufacturers suggest limiting the use of dry mode to just one hour at a time. If your air conditioner is especially good at extracting humidity, using dry mode for several hours could leave you with an insufficient amount of indoor moisture. Having excessively dry air in your house can cause uncomfortable symptoms.
- Dry, itchy eyes
- Dry throat
- Chapped lips
- Dry skin
- Frequent nosebleeds
Excessively dry air can also result in static electricity. Imagine shocking anyone that you touch after simply walking across your carpet. It is always best to have balanced humidity indoors rather than too little or too much.
The Benefits of Using Dry Mode
Dry mode is an incredibly handy feature for an air conditioner to have. Most modern ACs are built with this important function. Dry mode is efficient for regulating indoor humidity when outdoor humidity is high and for offsetting the extra moisture that is produced by lots of indoor traffic and moisture-generating activities. If you shampoo some or all of your carpets, dry mode can also keep your indoor air from feeling hot and heavy while your flooring dries. Moist air tends to feel quite a bit warmer than dry air does. This means that having this setting available on cold, humid days can mean the difference between feeling comfortable and not.
Dry mode also provides the important benefit of limiting mold. Keeping a clean and relatively dry home is the first step in preventing the development of mold and mildew. It also keeps active populations of bacteria and other living pathogens from spiraling out of control. Maintaining balanced humidity is an important step in maintaining acceptable indoor air quality and protecting resident health.
Beyer Air Conditioning & Heating proudly services residents of San Antonio, TX and the surrounding areas. In addition to HVAC installation, maintenance, and repair services, we offer VRF systems, indoor air quality services, and air duct cleaning.
