Dehumidifier
What it is
A wall-mounted humidistat control is recommended to measure room RH and reduce dehumidifier short-cycling.
Portable dehumidifiers use a fan to pass room air over the condenser coils to cool the refrigerant for cycling. The exhaust air will be slightly warmer than the room air.
All ENERGY STAR dehumidifiers include a built-in humidistat, a device that allows you to set the desired RH level that you would like for the room. Once the room reaches the desired RH level, the dehumidifier will cycle on and off automatically to maintain the level.
Seasonal use of dehumidifiers can remove moisture from damp basements and reduce fungal growth.
Keep in mind that dehumidifiers are fairly efficient space heating appliances (i.e., heating COP ~2 to 2.9) that also remove moisture from the room air.
U.S. Department of Energy · ENERGY STAR · National Park Service
Its parts
- Humidistat
- If your dehumidifier does not have a built-in humidistat or has a humidistat that does not show RH levels, consider purchasing a hygrometer (a gauge that measures relative humidity) separately and hang it near the dehumidifier. The hygrometer will measure RH levels and enable you to monitor when to turn the dehumidifier on and off.
- Condensate pump
- Most whole-home dehumidifiers are only equipped with a drain, which should be routed to a floor drain or condensate pump during installation by an HVAC professional.
Related pages
- Glossary: Dehumidifier
Its entry, and the guide's pages that use it.
- Indoor humidity
The right humidity range, humidifiers in winter, dehumidifiers in summer
Sources
- U.S. Department of Energy. Whole-House Dehumidification.
- ENERGY STAR. Dehumidifiers.
- National Park Service. Preservation Brief 24: Heating, Ventilating, and Cooling Historic Buildings.
- U.S. Department of Energy. Sensible and Latent Cooling Load Control (DOE Building America).