DEHUMIDIFIERS BUYING GUIDE

Dehumidifiers are electric appliances that reduce the humidity level in an enclosed space. A dehumidifier extracts moisture from the air to decrease humidity levels.

Too much moisture in the air can create an unhealthy environment and cause a range of issues including condensation, damp, bad odours and mould. They can also increase utility bills as you will require more energy to heat the moist air. Furthermore, it could cause damage to your furniture.

It’s an easy process to remove/clean/change the filters. Make sure you regularly clean the filter so it doesn’t get clogged. Just like a vacuum cleaner, a dirty filter reduces the effectiveness of a dehumidifier. Make sure you check the manufacturer’s instructions on how to safely clean the filter first though.

The moisture in your home comes from a range of sources such as cooking, washing machines and dishwashers, drying clothes and even just breathing!

If you often see the signs of excessive humidity such as excessive condensation on windows and mould patches on walls then it is likely that there is excessive moisture in the air. This excessive moisture can cause damage to wooden windows, wallpaper and fabrics within your home and allow unhealthy mould to grow. Excessive damp is often a problem with basements due to the reduced air flow. Garages can also suffer from damp that will cause cars and tools to rust. A dehumidifier will remove the excess moisture and help prevent these problems.

Relative humidity is a measure of how much water is in the air relative to the amount that air could hold if it was saturated. Relative humidity is expressed as a percentage. When relative humidity reaches 100% it is at the "dew point". In other words the air is "full" of water and that water will start to condense onto any surface. Warm air holds more water than cool air so as air cools relative humidity rises even though the physical quantity remains constant.

For every fall in temperature of 20°F/10°C the capacity of the air to hold water is halved. For example air at 80°F with a relative humidity of 50% will reach the dew point, 100% RH when it has cooled to 60°F.

Moisture condenses on the coldest surfaces: therefore although the humidity level may be high throughout your property, it will tend to condense on cold surfaces, typically windows or on the walls in rooms that are either North or East facing, rarely used unheated rooms, or rooms that are the only ones to have external walls. A desiccant dehumidifier is ideal for these conditions as they extract moisture at a constant irrespective of temperature whereas compressor dehumidifiers work best in warmer temperatures.

If it is the first time using a dehumidifier then it would be best practice to extract additional moisture, one room at a time. Once this process is complete, place it in a central position with doors slightly open to ensure it captures all the excess moisture. Also, Dehumidifiers rely on an unobstructed airflow to maximise their effectiveness. While some have vents on the top, most have them on the back. This means there needs to be a space between the dehumidifier and the wall. We recommended at least six inches around the dehumidifier.

No. The desiccant material does not expire and does not need to be topped up or replaced: desiccant dehumidifiers use a desiccant material, typically Zeolite, which absorbs water vapour from the air in a similar way to silica gel. A fan draws air into the dehumidifier and passes it through a section of a slowly rotating wheel which holds desiccant which dries the air.

The moisture is extracted from the desiccant unit by heating a portion of the wheel not being used to dry the air. At this point the moisture immediately drips out of the Zeolite and the process starts again.

Generally a relative humidity of 50% is comfortable for your home. This will protect your home and belongings, prevent mould growth and control the dust mite population. There is no real need to reduce humidity below the 45-50% mark. To do so will simply cost more in energy while serving no useful purpose.

The moisture is extracted from the desiccant unit by heating a portion of the wheel not being used to dry the air. At this point the moisture immediately drips out of the Zeolite and the process starts again.

If you dry your laundry in a very warm room, a powerful 20 litre compressor unit will be suitable. If you dry laundry in your kitchen, living room or spare bedroom then a desiccant unit will be a much better choice. Some desiccant units have a laundry function on them and remember that a desiccant unit will be blowing warm, dry air over your laundry as well as sucking the moisture out of your laundry.

A desiccant unit rated at around 7 litres per day will be best as is it will work as well in cool conditions as well as warm. Desiccant units are designed to run unattended for long periods of time in remote areas. They are supplied with a continuous drain option, as well as being able to collect in the tank, and are fitted with auto restart which means they do not need to be reset after a power cut, and can be left running on a plug timer if desired.

A desiccant unit rated at around 7 litres per day will be best as is it will work as well in cool conditions as well as warm.

Desiccant units are designed to run unattended for long periods of time in remote areas. They are supplied with a continuous drain option, as well as being able to collect in the tank, and are fitted with auto restart which means they do not need to be reset after a power cut, and can be left running on a plug timer.

Garages tend to be unheated therefore a desiccant unit is best as they extract moisture at a constant irrespective of temperature whereas compressor dehumidifiers only work well in warm (20+ degrees centigrade) temperatures. Furthermore, a desiccant can reduce humidity to as low as 40% which is below the rusting point of metal – making them ideal for storing machinery or tools. Desiccant units are designed to run unattended for long periods of time in remote areas. They are supplied with a continuous drain option, as well as being able to collect in the tank, and are fitted with auto restart which means they do not need to be reset after a power cut, and can be left running on a plug timer if desired.

Cellars tend to be quite cold therefore a desiccant unit is best as they extract moisture at a constant irrespective of temperature whereas compressor dehumidifiers only work well in warm (20+ degrees centigrade) temperatures. Desiccant units are designed to run unattended for long periods of time in remote areas. They are supplied with a continuous drain option, as well as being able to collect in the tank, and are fitted with auto restart which means they do not need to be reset after a power cut, and can be left running on a plug timer if desired.

Yes they can, some of our dehumidifier are fitted with HEPA filters which can extract mould, dust and bacteria out of the air to help with allergies and irritations.

This all depends on the product. On our site we offer a range of low energy dehumidifiers ensuring it doesn’t cost you a fortune to run. Also do not forget they can reduce your heating bills!

It removes excess moisture out of the air, walls and floors stopping mould and mildew reappearing.

Mould will not grow in humidity below 60% RH (Relative Humidity). By running a dehumidifier set to maintain humidity at 55% or lower so mould will not grow. Easy solution, buy a dehumidifier and keep mould at bay.

This all depend on how big your room size is and how much moisture you need to remove from the air. All our dehumidifiers on our site explain how much water can be extracted per day and where it is perfect for and what room size it will work well in.

Water is in the air everywhere. Certain activities in the home can increase the amount of moisture in the air including cooking, washing, showering and drying clothes in the house. Dehumidifiers help to reduce the amount of moisture/water in the air.

As long as the dehumidifier you choose is large enough for the area it is working in, and there are no specific damp problems, then a dehumidifier will normally reduce the humidity to the chosen level within a few days to a week. This timescale does not apply if the room has been flooded, in which case one or more dehumidifiers will be needed and possibly supplemented by air movers and other specialist equipment. This work is usually undertaken by specialised water damage specialists.

This depends on the dehumidifier type and size. For example a 10 litres manufacturer rated compressor dehumidifier will extract around 3-5 litres in normal domestic conditions in 24 hours depending of the relative humidity and temperature. A typical 8 litres desiccant will extract 7-8 litres in the same conditions being less sensitive to temperature variations. Once the dehumidifier is regularly used and the humidity has been reduced the amount of water removed daily will stay at a constant level.

The water collected in the dehumidifiers tank is called condensate, you can use this in your iron or to water the plants! However, it should not be drunk by humans or animals as it may contain traces of substances that could make you, your pets ill.

All portable dehumidifiers have a water collection container, often called a tank or a bucket, to collect the water extracted from the air. These buckets are quite small, to keep the overall size of the dehumidifier down, and need to be emptied at least once a day. Because it may not be convenient, or possible, to empty the bucket daily almost all portable dehumidifiers for home use are designed to allow the water to be drained directly as it is collected. This is known as continuous drainage. In the casing of the dehumidifier a small hole has been cut to allow a small hose (most of our units come with this hose in the box) to be attached to the dehumidifier through which the water can be drained. The water is drained by gravity alone so for effective continuous drainage the dehumidifier needs to be raised a foot or two above the floor and the hose run to a floor level drain.

Most domestic dehumidifiers will consume between 180 and 660 watts per hour – this equates to between 2 and 7 pence per hour at 2015 domestic energy prices. Bear in mind that the drier the air, the quicker the air will warm up when your heating is on. Therefore during the winter months the running cost of your dehumidifier will tend to be more than offset by the saving on your heating bill.

Used correctly, dehumidifiers can be a much more economical option for drying laundry than a tumble dryer. The latest energy efficient tumble dryers use at least 2500 watts per 120 minute cycle compared to an average of 880 watts for a desiccant dehumidifier for the same amount of time.

Consider that a desiccant dehumidifier positioned next to or below a clothes maiden will not only draw the moisture from the clothes but also blow warm, dry air over your clothes, drying them quickly – and there is no chance of your clothes being damaged in the process.

For example a 10 litres manufacturer rated compressor dehumidifier will extract around 3-5 litres in normal domestic conditions in 24 hours depending of the relative humidity and temperature. A typical 8 litres desiccant will extract 7-8 litres in the same conditions being less sensitive to temperature variations. Once the dehumidifier is regularly used and the humidity has been reduced the amount of water removed daily will stay at a constant level.

We know choosing a dehumidifier isn't an easy decision. Not sure what's best for you? We can take the guesswork out of decision-making. Call us at 0871 984 4416. We want to help make your indoors healthy and comfortable.