Dehumidifiers: Everything you would like and need to know if you want to buy or even if you already have a dehumidifier.

What is humidity?

First of all, let's start with the most basic. What is humidity or better relative humidity (SY or RH)? Simply put, to avoid confusion with mathematical formulas and related, relative humidity is the percentage of water vapor present in a given amount of air under certain conditions of pressure and temperature (for more read here Wikipedia).

How Does Humidity Affect Our Health?

When the percentage of humidity in an area is over 60%, fungal growth conditions are created that cause allergies and difficulty breathing. Moisture levels above 70% favor the growth of mold, which affects breathing, and cause difficulties in people suffering from arthritis and rheumatism. Research has shown a link between mold and asthma, as well as the appearance of moisture in combination with mold, which increases the risk of developing allergies. Harmful symptoms occur especially in children who are clearly more susceptible to the onset of respiratory problems.

Moisture levels above 70% favor the growth of mold and cause difficulties in people suffering from respiratory problems, allergies, arthritis and rheumatism.

What is a dehumidifier?

The dehumidifier is therefore an electrical device used to remove these water vapors from a space, in order to regulate its relative humidity to the desired appropriate levels (45% -55%), so that comfortable living conditions prevail and the burden is not burdened. our body (respiratory function, rheumatism, arthritis, etc.).

The ideal percentage of humidity for comfortable living in a space is between 45% to 55%.

What do we gain by having the ideal humidity in a space?

By ideally regulating the humidity in a space, we gain in:

  • Health: The humidity in a space contributes to the development of various health harmful microorganisms, fungi and mold that are harmful to our health (respiratory problems, allergies, etc.). Moisture also aggravates diseases such as rheumatism and arthritis.
  • Wellness: The humidity in a place causes a feeling of discomfort.
  • Economy: The use of the dehumidifier during the winter season serves to save energy and reduce heating costs as it takes less time to heat an environment due to low humidity. Also, with the use of the dehumidifier, we achieve an improvement in the sense of room temperature by the human body.
  • Lower building maintenance costs: The high percentage of moisture in an area creates mold on the walls that slowly destroys them and should be cleaned and maintained. Using the dehumidifier eliminates these effects.
Properly regulating the humidity of a room offers moisture and well-being.

What are the basic types of Dehumidifiers?

Depending on the air dehumidification technology, dehumidifiers are divided into two main categories:

  • dehumidifiers with compressor

The principle of operation of compressor dehumidifiers is similar to that of air conditioners. The humid air of the room passes through the cooling element of the dehumidifier. There the humidity of the air is liquefied and concentrated in the condensate container. The air then passes through a second heating element and after the temperature reaches the initial levels it returns to the room (about 1-3 ° C warmer than the existing one).

Dehumidifiers with compressor are distinguished for their very low consumption but also for the wide range of dehumidification capacity that can reach up to 50 Liters / 24 hours. Their main disadvantage is the relatively increased noise, which in recent years has been significantly reduced with the help of rotary compressors. Also the performance of these dehumidifiers is negatively affected by the low temperature of a room.

  • dehumidifiers with desiccant

The main component of desiccant dryers with zeolite is the zeolite disk which rotates at low speed. The humid air of the room passes through the tray, which thanks to the dehumidifying material retains moisture. To remove moisture from the tray, a portion of the air passes through a special device and after being heated through a resistor, it passes through the tray and absorbs the moisture that has accumulated in it. Finally, the air ends up in an exchanger where the absorbed moisture is condensed and ends up in the water tank of the device. In desiccants with Desiccant technology due to the lack of cold element and the existence of resistance the air you exhale is much warmer than that of the room (10 ° C to 12 ° C warmer than room temperature).

The dehumidifier Desiccants have a stable performance regardless of the room temperature and are the right choice for rooms where the indoor temperature can drop below 15 ° C and for rooms with insufficient heating.

Desiccant dehumidifiers are lighter, have a very low noise level (only fan noise is heard) but have a relatively high power consumption.

Desiccant dehumidifiers have a stable performance regardless of the room temperature while dehumidifiers with compressor very low consumption.

When to choose Dehumidifier with compressor and when with Zeolite?

Depending on the use and the space for which a dehumidifier is intended, the right choice of technology must be made in order to make the most of its potential.

For places where either very low temperatures prevail in winter (below 15 ° C such as warehouses, cottages, boats, etc.) or we have a requirement that our dehumidifier be as quiet as possible (bedrooms, libraries, etc.) good is to choose a Desiccant technology.

In all other cases it is good to choose one with a compressor mainly due to the much lower energy consumption but also a variety of additional functions that accompany them (filters, WiFi etc.).

What are the advantages and disadvantages of dehumidifiers depending on the technology they use:

with compressorwith desiccant
Energy Consumption+-
Low Noise-+
Operation at Low Temperatures-+
Additional Features+-
Performance not affected by the existing room temperature-+
Greater Dehumidifying Capacity+-

Generally remember: Desiccant either for small quiet or cold places. Compressor for energy savings in warm large spaces.

What Additional Functions Can a Dehumidifier Have?

In addition to their basic function, which is of course dehumidification, today's devices are slowly enriched with additional functions that either facilitate our daily life and use them or act as an adjunct to improving the atmosphere of our space.

Some of these features are:

  • Dust Filter: It is the basic plastic filter that retains most of the dust in the atmosphere before air enters the device. In this way, the basic air filtration is done and all subsequent filters (if any) are protected, as well as its internal components such as the liquefaction, heating element and the fan.
  • Ionizer: It is one of the most misunderstood functions. The ionizer is a function that negatively charges the air molecules, ie it creates negative ions in the air molecules. Negatively charged air molecules attract the positively charged particles of pollutants, bind to them electrically, which results in the formation of larger solid particles, which due to their increased weight can no longer float in the air, but fall down, from where can be removed by the usual cleaning methods (wiping, dusting, etc.).
  • WiFi: The WiFi function allows us to remotely control the dehumidifier through the App application on our Smartphone mobile from wherever we are, even outside the home. It requires a WiFi network in the area where the dehumidifier operates as well as mobile or WiFi data where we are with our Smartphone mobile.
  • HEPA filter: The HEPA filter filters even the finest dust and allergens, ideal for those who have allergies to household dust and not just dust.
  • Activated Carbon Filter - Carbon filters: Activated carbon filters very effectively filter harmful substances such as gasoline, solvents, insecticides, bacteria and germs that are responsible for various viruses such as H1N1, etc. Organic substances accumulate and are trapped on the surface of the activated carbon, thus cleaning the air coming out of the filters. The antibacterial action of the activated carbon filter removes and fights dust and all pathogenic microorganisms that are suspended in the atmosphere, thus protecting health and sensitive groups.
  • UVC lamp: The ultraviolet light of the UVC lamp, which is activated so much during the operation of the device, breaks the molecular bonds of microorganisms such as germs, viruses, fungi and bacteria that may be inside the dehumidifier, offering a perfectly healthy atmosphere in your space.
  • Drying Clothes: In the winter months when the sunshine is relatively limited and the outside humidity is at high levels, drying clothes is even more difficult. Dryers are an alternative but cause a relative wear on clothes due to the high temperatures they raise while some have high consumption (B Class). On the contrary, dehumidifiers are devices with low energy consumption and success the best possible result with the lowest cost without damage. Just put your dehumidifier in front of the spread clothes and choose to have the special program. If on the other hand it does not bother the work will be done just as well.
Dehumidifiers, in recent years, have evolved into state-of-the-art cleaning devices and a general improvement of the quality of the atmosphere of our space.

How Much Capacity of Dehumidifier Should I Choose for My Space?

Every dehumidifier on the market lists its dehumidification capacity in Liters per Day (L/Day 30oC RH80%)

To choose the litres of dehumidifier that we will buy, we must take into account the following factors:

  • The squares of the space we want to cover.
  • The insulation that our space has and if it presents moisture problems in the walls (eg mold, etc.).
  • The level of humidity in the area where the house is located.
  • The communication of the spaces between them, as it plays an important role in whether we will choose one or more dehumidifiers.

A general rule to follow is related to the dehumidifier fan, which can cover at least 4-5 times the air of our space within 8-10 hours of operation.

So in general it has prevailed that we need 1L/Day per 5sq.m. space, so for 40sq.m we need a dehumidifier 8L/Day. If your space is larger e.g. 100sq.m. you can choose one 20L/Day or choose two (2) of 10L/Day devices. In general, remember that the larger the dehumidifier, the more comfortable and relaxed it is and the faster it regulates the humidity in a room. Otherwise, when the dehumidifier is small, it works excessively without result and consuming higher amount of energy.

The greater the dehumidification capacity of a dehumidifier, the more comfortable and relaxed it is and the faster it regulates the humidity in a room.
The dehumidifying capacity of a dehumidifier in Liters per Day (L / Day) has nothing to do with the capacity of the water storage tank produced.

What maintenance does a dehumidifier need to function properly?

The basic maintenance that a dehumidifier needs is:

  • Very frequent cleaning of filters by the end user, at least every fifteen (15) days.
  • Periodic internal cleaning, inspection and maintenance by a specialist technician at least every 2 years.
Frequent cleaning of the dust filter of your dehumidifier, in addition to offering a dry and clean atmosphere to you, also prevents the creation of problems - damage to your device.

Where can Dehumidifiers be used?

The areas where dehumidifiers can be used are in homes, in rooms with humidity problems and more specifically in closets, in cottages for the maintenance of furniture and metal materials, in basements - warehouses for the storage of goods and objects, in sailboats - boats, in rooms with wooden floors but also in leaked buildings.

The indications that indicate the use of the dehumidifier are:

  • Drops inside the windows. When water vapor in the form of drops accumulates on the windows and frames.
  • Mold marks on the ceiling or in the corners of the walls. Especially in the bathroom where due to water vapor very often mold appears on the ceiling and in the corners of the walls.
  • Existence of bad smells and odors. The detection of a particularly characteristic odor in places such as garages and basements signals the presence of mold and the presence of moisture.

How much energy - electricity does a dehumidifier consume?

The energy consumed by a dehumidifier is given in its technical characteristics in Watt with the ideal conditions of 26.7 ° C and RH60% and ranges from 180W for an 8L with a compressor up to 660W for an 8L Desiccant. Multiplying this power by the operating hours of the dehumidifier we can find a relative consumption cost (KWh).

The dehumidifier only works until it catches the humidity target we have set for it, then it stops and starts again when the humidity rises above the desired level.

Can I use the air conditioner only as a dehumidifier?

Almost all air conditioners today have a dehumidification function, so they can also function as dehumidifiers. But attention is needed…

Air conditioners when operating as dehumidifiers:

  • They reduce the room temperature.

Air conditioners, because they have the compressor outdoors, do not produce this minimum total heating (equal to consumption) produced by a stand-alone dehumidifier, thus reducing the room temperature. This may be desirable and enjoyable in the summer but probably not in the winter. In addition, the dehumidification function to operate efficiently requires a room temperature above 18oC so if you use the dehumidification function of your air conditioner in winter, when the temperature starts to drop it will stop and the dehumidification will work. It is also considered quite energy-intensive in case another heating source is used for the room to simultaneously produce cooling for the air conditioner. Simply put, the dehumidification function of your air conditioner should only be used in summer.

  • The dehumidification function of the air conditioner has no humidity adjustment (humidistat).

In a classic and autonomous dehumidifier there is a choice of the desired percentage of humidity in the atmosphere. Air conditioners do not have this setting (only some very expensive and only in cooling mode) so the dehumidification function works without adjustment resulting in many times exceeding normal levels.

The air conditioners when they produce cooling at the same time remove the humidity of the room through the liquefaction that takes place in the cooling element of the internal machine. This is why air conditioners produce water that is drained through a pipe.