Dehumidifiers

Last updated: July 22, 2008.

Is damp climbing up your walls... and driving you up the wall? Few things make a home quite so unpleasant. Whether you have a damp problem with your building (rising or penetrating damp) or your moisture comes from cooking or drying laundry inside (condensation), the result can be a horrible musty smell, mold growing on your walls (and on your clothes), and a greater risk of respiratory illness. It can take time to sort out a major damp problem so what do you do in the meantime? One solution is to invest in a dehumidifier: an electric gadget that removes moisture from the air. Let's take a closer look at how they work!

Photo: A typical home dehumidifier. A machine like this costs about $200 (£100) and uses about 190 watts of electricity (slightly more than three ordinary 60-watt lamps burning at once), so it's reasonably economical to run. This one is a DEM10 made by DeLonghi. Other popular brands include LG, Frigidaire, Danby, and Soleus.

Vacuum cleaner meets air-con!

A dehumidifier is a bit like a vacuum cleaner: it sucks in air from your room at one end, takes the moisture out of it, and then blows it back out into the room again. The moisture drips through into a collection tank that you have to empty, from time to time. How is the moisture removed? That's where a dehumidifier is more like an air conditioning unit (sometimes called an air-con or HVAC, which stands for heating ventilating air conditioning unit), which, itself, works a bit like a refrigerator! Confused by all these appliances? Let's look inside a dehumidifier and find out what all the bits do.

Further reading

• Inside a dehumidifier: This photo on Wikimedia Commons shows you a dehumidifier taken apart.
• Keep your home free from mould and damp: Some practical advice from the UK's Dover District Council on reducing condensation problems in your home.