HUMIDITY
EFFECTS AND BENEFITS
DEHUMIDIFIER
AIR CONDITIONER
WHAT'S DEUCLIMA
WHY DEHUMIDIFYING
WHAT'S HUMIDITY
The air is a mix of various gas, in particular Nitrogen, Oxygen, Carbon Anhydride and watery vapour.
At standard room temperatures (0°C - 30 °C), the quantity of water in the form of vapour which can be present in the air, is only of few grams per cubic meter.
The atmospheric air may contain only one certain quantity of watery vapour; when it exceeds this quantity, you have the formation of fog, that is, very tiny drops of water floating in the air.
When the watery vapour, contained in the air, reaches its max. possible level, the air is called saturated air, meaning that it has 100% of Relative Humidity.
This max. possible quantity of watery vapour in the air, called saturated air, varies according to the different temperatures : it is approx. 4 grams per cubic meter at O °C and of 24 grams at 25 °C.
The Relative Humidity of a room is the ratio between the watery vapour quantity that is actually contained in the air and the quantity that the same would contain (at the same temperature), if it would be saturated , that is having 100 % of Relative Humidity.
This ratio is expressed in percentage. We could say that if at 25 °C , 1 cubic meter of saturated air contains 24 grams of vapour, at the same temperature one cubic meter of water having 50% R.H. will contain 24x50/100=12 grams.
At standard room temperatures (0°C - 30 °C), the quantity of water in the form of vapour which can be present in the air, is only of few grams per cubic meter.
The atmospheric air may contain only one certain quantity of watery vapour; when it exceeds this quantity, you have the formation of fog, that is, very tiny drops of water floating in the air.
When the watery vapour, contained in the air, reaches its max. possible level, the air is called saturated air, meaning that it has 100% of Relative Humidity.
This max. possible quantity of watery vapour in the air, called saturated air, varies according to the different temperatures : it is approx. 4 grams per cubic meter at O °C and of 24 grams at 25 °C.
The Relative Humidity of a room is the ratio between the watery vapour quantity that is actually contained in the air and the quantity that the same would contain (at the same temperature), if it would be saturated , that is having 100 % of Relative Humidity.
This ratio is expressed in percentage. We could say that if at 25 °C , 1 cubic meter of saturated air contains 24 grams of vapour, at the same temperature one cubic meter of water having 50% R.H. will contain 24x50/100=12 grams.
WHY DEHUMIDIFYING
EFFECTS AND BENEFITS
The R.H. in the room should range between 40 and 65%. Lower values, which can be obtained during the winter in heated rooms, may cause following problems: harsh dry throat, damages of electronic appliances, shrinking of vegetables, fruits, of paper and woods: in these cases, may be necessary to make the opposite operation of humidifying the rooms by using different systems such as a small water container on the radiator or humidifiers functioning with electric heating or with ultrasonic system.
However, the most difficult problem to solve is just the opposite, that is, an excess of relative humidity in the air.
High Relative humidity over 70-75 % in the long term may cause following problems:
1) Proliferation of micro-organisms such as moulds and bacteria, etc. with the ensuing bad smells;
2) Formation of water condensation on the cold surfaces such as glass windows, floors and walls;
3) Some uneasy physical feeling, especially when combined with high temperatures, which manifests itself n heavy sweating, blood pressure changes, etc.;
4) Increase of diseases concerning the respiratory system, disc pathologies and arthrosic – rheumatic problems;
5) Deformation of wood;
6) Deterioration of organic substances such as paper, foodstuff, vegetables, fruits, etc.;
7) Ill-functioning and damaging of electronic and mechanical appliances
8) Difficulties in the drying process of cloths, walls and pavements.
However, the most difficult problem to solve is just the opposite, that is, an excess of relative humidity in the air.
High Relative humidity over 70-75 % in the long term may cause following problems:
1) Proliferation of micro-organisms such as moulds and bacteria, etc. with the ensuing bad smells;
2) Formation of water condensation on the cold surfaces such as glass windows, floors and walls;
3) Some uneasy physical feeling, especially when combined with high temperatures, which manifests itself n heavy sweating, blood pressure changes, etc.;
4) Increase of diseases concerning the respiratory system, disc pathologies and arthrosic – rheumatic problems;
5) Deformation of wood;
6) Deterioration of organic substances such as paper, foodstuff, vegetables, fruits, etc.;
7) Ill-functioning and damaging of electronic and mechanical appliances
8) Difficulties in the drying process of cloths, walls and pavements.
WHY DEHUMIDIFYING
DEHUMIDIFIER
A dehumidifiers is a machine which removes the humidity from the rooms; this humidity is originated from the sources described here below: the relative humidity which is present in a room is represented by the balance of the humidity entering into a room (see below), which can be related or not with the relative humidity present in the room and the humidity removed by the dehumidifier which, instead, always related with the room relative temperature and humidity.
The dehumidifier, in its basis concept, is just a monoblock conditioner in which the room air, after passing through the evaporator (cold coil battery) where it is cooled and dehumidified (reduces the specific humidity, but it increases the relative humidity), passes then through the condenser (the warm coil battery) where it is heated up , thus strongly diminishing the relative humidity.
Practically, the balance conditions (relative humidity) are those obtained when the humidity entering into the room is equal to that humidity which can be removed by the machine.
The dehumidifier is a refrigerating cycle machiner: its functioning is based on a physical principle according to which the air, coming into contact with a cooled surface, it wets the surface by covering it with humidity in the form of condensed drops. What really happens is that a refrigerating machine maintains in a refrigerated state the coil through which is conveyed the incoming air that, in this way, is cooled and dehumidified. Then the air, passing through a warm heat-exchanger, heats up and returns in the room dehumidified and at a slightly higher temperature.
The dehumidifier, in its basis concept, is just a monoblock conditioner in which the room air, after passing through the evaporator (cold coil battery) where it is cooled and dehumidified (reduces the specific humidity, but it increases the relative humidity), passes then through the condenser (the warm coil battery) where it is heated up , thus strongly diminishing the relative humidity.
Practically, the balance conditions (relative humidity) are those obtained when the humidity entering into the room is equal to that humidity which can be removed by the machine.
The dehumidifier is a refrigerating cycle machiner: its functioning is based on a physical principle according to which the air, coming into contact with a cooled surface, it wets the surface by covering it with humidity in the form of condensed drops. What really happens is that a refrigerating machine maintains in a refrigerated state the coil through which is conveyed the incoming air that, in this way, is cooled and dehumidified. Then the air, passing through a warm heat-exchanger, heats up and returns in the room dehumidified and at a slightly higher temperature.
WHY DEHUMIDIFYING
AIR CONDITIONER
In the rooms where there are heat producing causes (electric appliances, insulation systems etc.), and only in these cases, the air conditioner can exert also a dehumidification function when it is cooling; when, instead, it is not exerting its cooling function, it has no dehumidification capacity (with relative humidity increasing) and , in these cases, it is necessary to use exclusively a dehumidifier to remove the humidity.
The air expelled from the air conditioner, in fact, is considerably cooled with consequent reduction of the specific humidity but with a great increase of the relative humidity.
For instance, one air conditioner lets in the room air at about 13 °C but with relative humidity at 95%. Therefore, if there are sources of heat in the room, the room air is heated up, thus considerably reducing also the relative humidity; if this is not the case, the room air temperature tends to diminish and consequently the relative humidity will increase: in all these cases, the air conditioner is unsuitable for reducing the humidity.
This "post-heating" function is proper, instead, of the dehumidifier, which is, therefore, required in many rooms and closed places during the middle seasons and, during summer, may be necessary in old houses, canteens and taverns, in the drying of new buildings, in museums, libraries, etc.
In winter time, the dehumidifier is the only reasonable system suitable to remove the relative humidity in our houses in which there may be no natural air exchanges or it may not be convenient to open the rooms to let in fresh outdoor air because of the energy cost necessary to reheat it afterwards.
The dehumidifier is, moreover, designed to obtain the optimal dehumidification with minimum level of energy consumption, thanks to its direct control of the humidity due to the presence of an automatic humidistat.
In all these cases, the dehumidifier produces the following benefits: the fast and radical elimination of bad smells, of moulds, of the phenomenon of condensation on the walls and floors, and a healthy wellness feeling in the persons, especially in those affected by respiratory and orthopaedic pathologies.
The air expelled from the air conditioner, in fact, is considerably cooled with consequent reduction of the specific humidity but with a great increase of the relative humidity.
For instance, one air conditioner lets in the room air at about 13 °C but with relative humidity at 95%. Therefore, if there are sources of heat in the room, the room air is heated up, thus considerably reducing also the relative humidity; if this is not the case, the room air temperature tends to diminish and consequently the relative humidity will increase: in all these cases, the air conditioner is unsuitable for reducing the humidity.
This "post-heating" function is proper, instead, of the dehumidifier, which is, therefore, required in many rooms and closed places during the middle seasons and, during summer, may be necessary in old houses, canteens and taverns, in the drying of new buildings, in museums, libraries, etc.
In winter time, the dehumidifier is the only reasonable system suitable to remove the relative humidity in our houses in which there may be no natural air exchanges or it may not be convenient to open the rooms to let in fresh outdoor air because of the energy cost necessary to reheat it afterwards.
The dehumidifier is, moreover, designed to obtain the optimal dehumidification with minimum level of energy consumption, thanks to its direct control of the humidity due to the presence of an automatic humidistat.
In all these cases, the dehumidifier produces the following benefits: the fast and radical elimination of bad smells, of moulds, of the phenomenon of condensation on the walls and floors, and a healthy wellness feeling in the persons, especially in those affected by respiratory and orthopaedic pathologies.
WHY DEHUMIDIFYING
WHAT'S DEUCLIMA
Classic dehumidifiers when used in a room ambient produces a temperature increase. The heat released in the ambient is exactly the absorbed electric energy plus the latent heat released when the steam that is in the air become water. If the humidity in the ambient air come from drying materials, the latent heat is in a big part compensated by the evaporating process that needs heat.
As known, the functioning of a traditional dehumidifier is as follow. The inlet air, passes through the Evaporator of refrigerant machines, the cool coils, where reduces the temperature and the absolute humidity.
Then the air passes through the condenser where increases the temperature and return in the room ambient at an higher temperature but with a much reduced Relative Humidity. Usually the running of the machine is controlled by a dehumidistat, which can be placed inside the machine or on the wall. This control may be mechanic or electronic type.
FRAL designed and produces some special machines which can control both Temperature and Humidity, that are very useful when the process not allows an increased temperature.
This machines have two condensers (the coil where heat is transferred): the first one is like in a traditional dehumidifier, another one located out of room ambient (or in the ambient but with outdoor cooling air in mono-block type). If the humidity is over the R.H. set point, machine starts in traditional configuration, if temperature increases over the Temperature set point, the machine starts in cooling functioning (if it is OFF), or commutates from drying to cooling system if already working.
There are three standard models, as below described, in which the control of temperature is ON/OFF, but FRAL produces currently special machines of bigger capacity in which the control of temperature can be of proportional type.
As known, the functioning of a traditional dehumidifier is as follow. The inlet air, passes through the Evaporator of refrigerant machines, the cool coils, where reduces the temperature and the absolute humidity.
Then the air passes through the condenser where increases the temperature and return in the room ambient at an higher temperature but with a much reduced Relative Humidity. Usually the running of the machine is controlled by a dehumidistat, which can be placed inside the machine or on the wall. This control may be mechanic or electronic type.
FRAL designed and produces some special machines which can control both Temperature and Humidity, that are very useful when the process not allows an increased temperature.
This machines have two condensers (the coil where heat is transferred): the first one is like in a traditional dehumidifier, another one located out of room ambient (or in the ambient but with outdoor cooling air in mono-block type). If the humidity is over the R.H. set point, machine starts in traditional configuration, if temperature increases over the Temperature set point, the machine starts in cooling functioning (if it is OFF), or commutates from drying to cooling system if already working.
There are three standard models, as below described, in which the control of temperature is ON/OFF, but FRAL produces currently special machines of bigger capacity in which the control of temperature can be of proportional type.