What is a dehumidifier?

A dehumidifier is simply a machine that extracts moisture from the air and keeps the RH (Relative Humidity) at a safe level.

You need some moisture in the air otherwise you end up with symptoms such as  cracked lips etc.

If the air around you is too moist then problems such as mould, mildew and condensation can occur. This could lead to respiratory problems for the person living in these conditions.

How much water does a dehumidifier extract per day?

Most manufacturers state that their appliances extract anywhere from 8 – 12 litres of moisture per day.

These figures are probably only likely in very damp areas with the machine running continuously.

Most dehumidifiers turn ‘on’ and ‘off’ automatically once the required humidity level has been reached. Therefore the appliance is not working continuously and actual daily extraction will likely be around 2-3 litres per day.

How low a humidity level can the average domestic dehumidifier reach?

Very low humidity levels are only required for specialised industrial operations.

A typical house should have humidity levels of around 50%.

Some dehumidifiers such as the Meaco Portable Compact Dehumidifier DD8L can reach relative humidity as low as 35% when set on ‘Laundry Mode’ which is useful for drying clothes.

On average though, a domestic dehumidifier will get RH down as low as 45-48%.

How much does a dehumidifier cost to run?

Typically most domestic dehumidifiers are fairly cheap to run.

It all depends on how much power the dehumidifier needs to run however most reviewers state that the average running cost is between 4p-7p per hour.

Bear in mind that water extraction is linked to power consumption so that a dehumidifier that uses more power is also able to extract more water.

How noisy is a dehumidifier?

Most dehumidifiers have several settings such as low, medium and high.

Low settings are generally very quiet and may be compared to a running computer.

Medium settings typically operate at the same volume level as you would find in a library.

High settings are generally in the 45dB range which is comparable to a desk fan at high speed.

Most dehumidifiers would normally operate mostly on their medium settings.

Is the water collected by dehumidifiers safe for drinking?

The short answer is no.

Water collected by dehumidifiers are not safe for drinking. Remember that spores of mould, fungi, viruses and bacteria etc are also collected by the dehumidifier therefore all collected water should be disposed of.

Can a dehumidifier help control or relieve my allergy symptoms?

Since allergies are often caused, or irritated, by a moist environment a dehumidifier could indeed help those suffering from allergies.

A humid area is a breeding ground for mould, mildew, dust mites and bad bacteria all of which can trigger allergy symptoms.

By introducing a dehumidifier you make the air in your environment cleaner and healthier which should help to relieve your symptoms.

Where should I place my dehumidifier?

For dehumidifiers that work in a single room the appliance should be placed at least 6 inches out from a wall so that air flow is not impeded.

Dehumidifiers that control a larger area such as a whole house are best left in the hall which connects as many rooms as possible.

In two storey houses you may have to move the dehumidifier between the downstairs and upstairs hall.