In recent years, dehumidifiers have become mainstream products that you can find at any DIY store or on the Internet. If your home is wet, in addition to the work necessary to solve this problem, an electric dehumidifier is the ideal solution to clean the air. But how to make the right choice among the different techniques on the market and on which criteria to base your purchase?
The different types of dehumidifiers
Currently you find 2 very different kinds of electric dehumidifiers:
- The condensation dehumidifier: The humid air is brought by a fan to a condenser. The condenser is in the form of a coil containing a refrigerant gas compressed by a compressor. (It's the same principle of operation as a refrigerator). The water vapor contained in the moist air condenses on the colder condenser. As water flows, it flows to a recovery tank. The air that comes out is drier and heated by the compressor.
The hotter and humider the air, the more efficient the dehumidifier will be. Below 10 to 12°, it loses its yield. Some sophisticated models are optimized to operate even at low temperatures.
- The dehumidifier with absorption or air dryer: The moist air is supplied by a fan to a honeycomb wheel coated with silica gel. Silica gel is hygroscopic, that is, absorbs moisture from the air. Under the effect of centrifugal force, the water thus recovered is discharged to a reservoir. The energy used to spin the wheel heats the air and regenerates the silica gel before venting to the outside. The air it rejects is generally warmer (+5 to 6°) since 80% of the energy used is returned in heat.
Silica gel has a service life of approximately 54,000 hours, or 6 years of continuous operation. It is advisable to clean the wheel regularly so that the dust does not affect the absorption capacity of the gel.
It can work from 0° C.
How to choose your dehumidifier?
The best dehumidifier is the one that fits your needs! The first thing is to define these, while taking into account that the figures announced by all manufacturers are based on tests performed at 30° in air with a humidity of 80%. In a "more normal" environment, yields are therefore lower.
- Tgate, volume and hygrometry of the workpiece: Depending on whether you want to dehumidify your bathroom or indoor pool, you will not buy the same device. It is the capacity of the device that will guide you, that is to say, how much water can it extract in 24 hours.
For example: Extraction 10 l / 24 h - For a room of 20 m² - 50 m3.
- The temperature of the room: If the room to be dehumidified is cool or cold, a condensing model will quickly reach its limits. Then go to a dryer.
- The sound volume: A condensing dehumidifier due to the presence of a compressor is louder than a dryer. But it is a little less effective. Staying between 40 - 45 dB you stay in the field of reasonable and sustainable.
- Energy consumption: It depends on the power of the device. But a dryer consumes less than a condensing dehumidifier.
- Hygrostat function: It will allow you to set the desired humidity level. The unit will automatically stop when it reaches the target to get back on the road when the humidity rises. Depending on the model, it is a simple button to turn or an electronic system with a LCD screen and / or a programmer.
For a home, the ideal relative humidity is between 45 and 65%.
- Tank capacity and permanent drainage: Depending on the power of the device, the tank is more or less important. When full, the dehumidifier automatically shuts off. Some models allow you to permanently evacuate water through a pipe. You do not have a pan to empty and the dehumidifier can work continuously.
The price depends of course on these criteria. But not only... Design also comes into play. Depending on whether you install it in the living room or in the basement, its appearance and discretion (sound level) may be more or less important.
Some models are equipped with dust and / or antibacterial filters to clean the exhaust air.
To note: You can also find small thermoelectric dehumidifiers (Peltier effect). He exploited the physical phenomenon discovered by the physicist Jean-Charles Peltier in 1834. Under the action of the passage of an electric current on the conducting materials of different natures, there is a displacement of heat. Water condenses on the coldest part and evacuates to a reservoir. If they are very quiet, they are not very powerful (Between 0.2 and 0.6 l / 24 h)