DESCRIPTION OF THE INVENTION

NAME OF THE INVENTION

METHOD TO REMOVE WATER VAPOUR CONDENSATION ON WINDOWS AND APPARATUS TO CARRY THAT INTO EFFECT

FIELD OF THE INVENTION

The invention relates to the method of removal of the unfavourable water vapour condensation on the interior surfaces of the windows in the heated rooms, particularly in the buildings designed for permanent residential use, which results from the drop of the surface temperature on the interior window surfaces under dew point temperature of the interior air and the apparatus to carry that method into effect.

BACKGROUND OF THE INVENTION

The basic requirements that all buildings designed for residential use and all their related structures must fulfil during economically reasonable lifetime are hygiene and protection of the human health. The building envelope structure should be constructed thus, that the temperature of their interior surface is always higher than the dew point temperature of the interior air. The air change rate in the room must not be lower that the minimal hygienic recommended mean air change rate. If those requirements are met, the condensation of the water vapour contained in the interior air does not occur on the interior surfaces of the building envelope structure. At specific temperature and humidity state of the interior and exterior environment, the condensation can occur on the interior surfaces of the windows. Technical standards tolerate this occurrence, however the faultless functionality of the structures must be ensured when condensation on their surfaces occur. Several methods are known how to prevent this occurrence and how to avoid the unfavourable results of the condensation. At present, the windows with almost zero gap permeability are used normally. Hygienically recommended mean air change rate of the indoor environment (i) is ensured by utilising micro ventilation position, which ensures the air change through the sash gaps of the openable window sashes, which ensure the air change through the sash gaps of the window in the micro ventilation position. Efficiency of this method is in that through the window gaps into the room flows the cold exterior air, whose relative humidity is decreased by warming up to the room temperature and thus the dew point temperature of the interior air and the risk of condensation are decreased. The disadvantage is in the fact that utilising of the micro ventilation position of the openable window sashes looses reasons for the

utilisation of the seals with low gap permeability, which shall lower heat losses caused by natural infiltration. Other method is utilisation of the windows with ventilation gaps. The clear opening of the gap is adjustable. The principles of the method and its disadvantages are the same as in the previous method. Intensive short-term ventilation of the room through fully opened window sashes is utilised as well. The main disadvantage is low comfort of the solution. Other method is making use of the air conditioning unit, which is capable of regulating the parameters of the interior air to the required values. The disadvantages are high purchase costs and operational costs.

SUMMARY OF THE INVENTION

The object of the invention is to avoid listed disadvantages. According to the invention, this problem is solved by separating window interior surface (1) from the warm interior air(4) by the layer of the conditioned exterior air (7), which flows at the window interior surface (1). The layer is created by that the cold exterior air (6) is extracted from the outdoor environment (e), then it is transported through the heat exchanger (10) to the upper edge of the window interior surface (1) and is driven so that it flows downwards the window interior surface (1). At the same time the warm interior air (4) is extracted out of the room and is driven to the outdoor environment (e) through the heat exchanger (10). The principle of the conditioning of the cold exterior air (6) is that by flowing through the heat exchanger (10) its temperature is raised at unaltered absolute humidity and thus the relative humidity is decreased. In the heat exchanger (10) the transfer of the heat from the outgoing humid warm interior air (4) to the incoming cold exterior air (6) occurs wherein the heat transferred by the outgoing humid warm interior air (4) consists of the heat transferred by the convection and the condensation. The principle of the efficiency of this method is that the dew point temperature of the conditioned exterior air (7) flowing at the window interior surface (1) is safely lower than the temperature of the window interior surface (1). Concurrently with mixing of thus flowing conditioned exterior air (7) and warm interior air (4), the quality of the warm interior air (4) improves from the aspect of the water vapour condensation risk on the interior surfaces of the structures. It is advantageous to extract the warm interior air (4) under the ceiling of the room, where the quality of the air is lowest by the hygienic point of view. It is advantageous to drive the conditioned exterior air (7) onto the surface of the window in the manner that it flows from the upper edge of the window downwards at the entire window interior surface (1). The flow of the conditioned exterior air (7) downwards is supported by the difference of the bulk density between the conditioned exterior air (7) and the surrounding interior air, because the temperature of the conditioned exterior air (7) is lower than the temperature of the interior air and therefore its bulk density is higher than the bulk density of the interior air. It is advantageous to extract in the cold exterior air (6) in the manner, that the layer of the ascending flow of the exterior air (8) which occurs at the window exterior surface (2) at calm exterior environment (e) is captured, wherein the flow of this layer upwards is caused by the difference between bulk density of the layer of

the exterior air which is in contact with the window exterior surface (2) from which the heat is transferred to this layer and the bulk density of the cold exterior air (6).

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be best understood from the accompanying drawings in which: fig. 1 represents the vertical section of the upper part of the window, the fundamental parts and the principle of the performance; fig. 2 represents the scheme of the apparatus, its components and their possible configuration; fig. 3 represents the vertical section of the window, the apparatus embedded between the upper part of the window and head of the opening, together with the representation of the function.

DESCRIPTION OF THE PREFERRED EMBODIMENT

The method, which is the subject of the protection represents the solution of the problem of which typical example is the condensation of the moisture on the cold window surfaces in a unit of the apartment building, in which the original wooden double windows with high air leakage were replaced by windows made of plastic profiles with isolation double glazing with air leakage close to zero. The replacement of the windows diminished the heat losses caused by transmission and infiltration, but started the problem with the condensation of the moisture on the cold interior surfaces. This problem will be safely solved by the method and the apparatus, which are the subject of the protection. The apparatus 18 will be embedded between the windowhead 3 and the upper part of the window frame 17. It comprises the group, which by the exterior air ventilator 12 extracts the cold exterior air 5_from the upper part of the window exterior surface 2, drives it through the heat exchanger 10 to the window interior surface 1 and drives it to flow onto the window interior surface 1 towards its lower edge. The next part of the apparatus is the group, which by the interior air ventilator H extracts the warm interior air 4 from the upper part of the room, in the heat exchanger 10 decreases its temperature and humidity and transports thus conditioned interior air 5 to the outdoor environment e. The common part of both groups is the heat exchanger 10, in which the outgoing warm interior air 4 transfers the heat to the incoming cold exterior air 6 wherein the temperature of the incoming cold exterior air 6 increases at the unchanged content of the water vapour which decreases its relative humidity. The window interior surface 1 is isolated from the warm interior air 4 by the air layer, created by the directed flow of the conditioned exterior air 7, the dew point temperature of which is lower than the surface temperature of the window interior surface 1, therefore the condensation of the water vapour contained in the warm interior air 4 does not occur on the window interior surface 1. The condensate 9, originating in the heat exchanger 10 caused by the condensation of the water vapour which is

contained in the outgoing warm interior air 4 is captured in the condensate container 15. By the operation of the apparatus, the mixing of the incoming conditioned exterior air 7 with the warm interior air 4 occurs, therefore the quality of the interior air is improved from the point of view of the water vapour condensation risk on the interior surfaces of the structures.