Do Furnaces and Heaters Dry Out the Air? (2024)

FAQs

Does a heater dry out the air? ›

While heating up the air will lower the relative humidity (since relative humidity is dependent on temperature), the absolute humidity shouldn't change.

A standard furnace, also called an atmosphere furnace, draws air from inside your house to work. Because the furnace consistently relies on air to burn, it will also pull cold, dry air from outdoors, which in turn reduces your house's humidity.

Turning on your gas furnace makes your home feel warmer but can also dry out the indoor air. Dry air can carry a whole host of ailments, like dry skin, cracked lips and make you more vulnerable to getting sick. Here's why your gas furnace dries out your home's air and what you can do to counter it.

Use a humidifier.

Running a humidifier in your home will add moisture to dry, heated air. The moist air will help keep your skin, mouth, and nose lubricated, and helps prevent those nasty static shocks. Your goal is to aim for a comfortable home humidity level of between 30% and 50%.

Indoor Heat Is a Sneaky Source of Dehydration

All the heat pumped into your office or home keeps the building warm, but “indoor air is really dry,” says Antonucci.

Your home should sit somewhere between 30 and 50 percent humidity. If it's measuring below 30 percent, you may need to invest in a humidifier to remedy the dry air symptoms.

Using drying agents like silica gel, desiccant dehumidifiers pull moisture out of the air by forcing it through water-absorbing gel packs. These systems are typically less heavy and quieter than the refrigerant types, and one big benefit is that desiccants work equally well in cold temperatures.

Most manufacturers use compressed air dryers as one of the methods for removing moisture.

Heaters do not take moisture out of the air itself. However, once the air is warmed past a certain point, it can absorb a lot of moisture. It then draws moisture away from your body, making your skin feel much drier. Essentially, heaters cause much lower levels of relative humidity.

Can the air in your house be too dry? ›

When the air is too dry, static electricity begins to build up. That shock of static electricity could be a sign your home's air is too dry. Dry Lips and Skin: If you feel like your skin and lips are overly dry, this could be further indications that the air in your home does not have enough moisture.

Without having to spend a dime, you can increase your home's humidity by placing a metal or ceramic bowl of water on top of your floor registers or radiant heating unit. The water will evaporate into humid air. On a sunny day, place a bowl or vase filled with water on your windowsills.

“When you turn on your heater for the first time, dust, pollen and other indoor allergens may cause sinus congestion,” says Dr. Anuja Vyas, a board-certified pulmonary disease doctor with Sharp Rees-Stealy Medical Group. “These symptoms may make you feel sick.”

Breathing dry air can irritate respiratory ailments, and in some cases lead to asthma, bronchitis, the common cold, the flu and even nosebleeds. Because the majority of our breathing is done through our nose, cold, dry air can cause the inside of our nose to become dry and irritated.

Yes. In fact, many of the symptoms of seasonal illnesses are mimicked by the body's reaction to breathing in allergens (even if you are not prone to allergies) and sitting in hot, dry conditions.

The ideal relative humidity level for maximum comfort and health is between 40 and 50 percent, and anything below 30 percent is considered too dry. Humidity levels naturally drop along with outdoor temperatures as cold air is unable to hold the same amount of moisture as warm air.

Open Windows to Let Fresh Air In. While it may seem counterintuitive, it is actually helpful to open the windows and remove the stale, dry air from your house. Open windows during the daytime to let the fresh air in. It will help you breathe easy, and your skin won't feel that dry and itchy.

How do you tell if there is too much moisture in the air? ›

How can you tell when the humidity is too high inside your home? There are a couple of telltale signs like clammy skin, foggy windows, and a heavy yet warm atmosphere. But you can also smell mildew or musty odors when your home is much too humid, which comes from moisture buildup.

High humidity in a house can be caused by many things, but the biggest reason is poor ventilation—in other words, air isn't being circulated properly, which causes the air in your house to become stagnant and humid. The other major reason? Too much air exchange with the outside.

Use dehumidifiers and air conditioners, especially in hot, humid climates, to reduce moisture in the air, but be sure that the appliances themselves don't become sources of biological pollutants. Raise the temperature of cold surfaces where moisture condenses. Use insulation or storm windows.

If the furnace is the only new item you've added in the house since this problem became evident, then the humidity problems are probably the result of reduced air exchange between air inside the house and air outside the house. Fuel burning furnaces require a large amount of air to combust the fuel properly.

Preventing mold through heating

It makes sense that people want to save on heating cost, but one of the best mold prevention techniques is keeping your heating on. If you seriously want to avoid mold in your home then avoid rooms cooling completely.

The first place to check for moisture is the ground near your home. The ground slope is easy to see, but to be sure the moisture is going away from — and not toward — your home, pour a bucket of water near the foundation. If the water moves toward your home, you could have a problem.

The easiest way to measure your indoor humidity level is by using a hygrometer. A hygrometer is a device that serves as an indoor thermometer and humidity monitor.

Ideal in-home humidity levels should hover around 45%.

Anything under 30% is too dry, and over 50% is too high.

When you switch on an electric heater, the air that blows from it depletes the amount of moisture present in the air around you. This turns the air dry and can, in turn, cause itching because of the dryness of your skin.

Can a heater dry a damp room? ›

Fan heaters heat up the air that is already present in the room, meaning it also absorbs more moisture. Using a heater blower before opening windows and doors therefore means more moisture can be extracted from the inside. Infrared heaters with an IP code can be used in damp rooms like a bathroom.

No Dry Heat. Unlike conventional heaters that draw moisture out of the air as a part of their heating process, infrared heaters don't produce dry heat. This way you can avoid uncomfortable side effects such as itchy eyes and throat.

The idea is that the heat of the air from the heater will pull water from the dish into the air, thereby adding humidity to dry, indoor air. This was particularly used before furnaces and humidifiers were invented, and is still used occasionally in sickrooms where a chest cold or sinusitis is at work.

Use dehumidifiers and air conditioners, especially in hot, humid climates, to reduce moisture in the air, but be sure that the appliances themselves don't become sources of biological pollutants. Raise the temperature of cold surfaces where moisture condenses. Use insulation or storm windows.

The World Health Organisation guidelines suggest 21 degrees in a living room and 18 degrees in the bedrooms, falling lower at night and when you are out.