Instruction manual

UNDERSTANDING AND USING A DEHUMIDIFIER

How does a dehumidifier work?

There are four types of dehumidifier sold to the domestic market in the UK - Compressor, desiccant (this

dehumidifier), peltier and silica gel.

A desiccant based dehumidifier draws the air in from the room over a filter and passes it over a rotating

wheel that is full of a material called Zeolite which absorbs the excess water out of the air. The wheel is

now saturated and needs to be regenerated. A heater in the base of the dehumidifier blows warm, dry air

over the Zeolite to force the moisture out of the wheel. The Zeolite is now ready to dry again and the

warm, wet air from the wheel hits a metal surface which ensures the excess moisture condenses and the

water drips into the internal tank. The heat used during the drying process is mixed with the dry air to

ensure that the air that comes out of the dehumidifier is not just drier but 10-12°C warmer than the air that

came in.

Why does water appear on my windows/cupboards/walls?

It is a basic law of physics that if the surface is cold enough and if there is enough water vapour in the air

then it will condense. This means in the case of windows whether they are double-glazed or not that if the

windows are cold enough and there is enough moisture in the air then condensation will occur.

Where does this water come from?

We all produce water by drying clothes indoors, the boiling of vegetables, showering, rain, calor gas

heating and making cups of tea all produces moisture. It is just an on-going process that never stops.

Can I just get rid of it by opening my windows?

This is fine on a nice summer’s day but in winter opening your windows will just result in you losing the

heat from your central heating and creating draughts. This is a waste of money and if it is raining will just

let more moisture in. You might as well just throw fivers out of the window.

Will a dehumidifier do the whole house?

A dehumidifier creates a volume of dry air in as large a space as its fan can effect (this dehumidifier can

control up to a small 5 bedroom house). After that it will be helped by the fact that damp air will always

migrate to dry places. As long as you leave all of the internal doors open a correctly sized dehumidifier

will prevent condensation and mould from appearing around the whole house.

What about the black spots of mould on my window and bathroom sealant?

Mould occurs around 68% humidity, condensation occurs at 100%. As you can see from this you can

have mould but still have clear windows. A dehumidifier will prevent the mould from getting any worse

and once you have cleaned the mould away, it will stop it from coming back.