Our old central air conditioner still works, but our house often seems too humid indoors. We set the thermostat lower, but it does not help a lot.How can we reduce the humidity and improve comfort?—Michael T.
First, try to reduce the humidity you’re already producing. The kitchen and bathrooms are the greatest contributors to high humidity levels. Make sure your stove’s exhaust hood is ducted outside, not into the attic, and run the fan when cooking, especially while boiling water. Run the bathroom vent fan whenever showering or bathing. Don’t turn it off as soon as you are done because there is much residual moisture in the air.
Some of the new, quiet bathroom vent fans have humidity level sensors to run long enough to exhaust the moisture, but not too long to waste electricity. You can also try a simple countdown timer for your current bathroom fan—set it for 30 minutes, then turn the fan off.
There may be other rooms in your house where you find the humidity level to be uncomfortable. A portable air conditioner or mini heat pump, which can be moved from room to room and vents outdoors through a window, can provide spot cooling and dehumidification.
How fans save
If you can get the indoor humidity level low enough, it is often possible for your family to get by with a much higher thermostat setting and ceiling fans. The air movement from a fan increases evaporation and creates a “wind chill” effect for added comfort. Make sure the ceiling fan rotates to blow the air downward during summer.
Proper sizing of a central air-conditioning system is critical for low humidity and comfortably cool indoor air. If it’s time to replace your old system, consider a two-stage model with a variable-speed blower motor.
With the matching smart thermostat, these models are designed for efficiency and humidity control. You can set both the desired temperature and humidity settings. The air conditioner will run as normal to cool the air to the desired temperature. Once that temperature is met, the blower speed slows down to provide more dehumidification.
Don’t forget to fix leaky gutters and downspouts. If rainwater leaks out and saturates the ground around your house, some of that moisture will eventually migrate indoors.
Hot-weather AC modifications could save money
If you’re not ready to replace your old air-conditioning system, a contractor may be able to change some settings to slow the blower motor on your current unit. This will dehumidify more but will likely reduce its efficiency somewhat. If the lower humidity level allows you to set the thermostat higher and still be comfortable, you should save electricity overall.
Mail requests and questions to James Dulley, Kentucky Living, 6906 Royalgreen Drive, Cincinnati, OH 45244, or visit www.dulley.com.