JP5921213B2 - Desiccant ventilation fan and its control method - Google Patents

Description

The present invention relates to a desiccant ventilation fan that ventilates and dehumidifies a room and suppresses a temperature rise, and a control method thereof.

As a result of the revision of the Building Standards Law, ventilation of 0.5 times / h or more is obligated in ordinary households as a countermeasure against sick house. A ventilation system for ventilating a house includes a desiccant ventilation fan having a dehumidification ventilation mode that ventilates and dehumidifies a room and suppresses a temperature rise, and a specific example is described in Patent Document 1.
The desiccant ventilation fan of patent document 1 operates a desiccant rotor, reduces water | moisture content from the external air supplied indoors through an air supply path, operates a sensible heat exchange rotor, and takes heat from the external air which goes indoors. .

By the way, since the operation of the desiccant rotor and the sensible heat exchange rotor involves power consumption, the power consumption can be suppressed if the desiccant rotor and the sensible heat exchange rotor are stopped and only ventilation is performed. Therefore, from the viewpoint of energy saving, it can be said that a desiccant ventilation fan capable of performing the dehumidification ventilation mode is preferably provided with a ventilation single mode for performing only ventilation.

JP 2007-85680 A

However, if the desiccant rotor and the sensible heat exchange rotor are simultaneously stopped when the dehumidification ventilation mode is switched to the single ventilation mode, the sensible heat exchange rotor of the supply passage that has been cooled by the operation of the sensible heat exchange rotor in the dehumidification ventilation mode will be stopped. A phenomenon occurs in which condensation occurs on the downstream side.
This is because the dehumidification ventilation mode is generally performed in summer, and when the desiccant rotor stops, the hot and humid outside air taken into the supply passage passes through the supply passage without being dehumidified by the desiccant rotor. Because.
Condensation promotes the growth of mold, bacteria, and the like, which causes hygiene problems.
This invention is made | formed in view of this situation, and it aims at providing the desiccant ventilation fan which suppresses that an air supply path condenses, and its control method, when switching ventilation mode.

The desiccant ventilation fan according to the first aspect of the present invention is directed to a sensible heat exchange rotor that transfers heat from an air supply path that sends outside air into a room to an exhaust path that discharges air in the room, and the exhaust from the air supply path. In a desiccant ventilation fan that ventilates the room, having a desiccant rotor that moves moisture to the path, and a control means that controls the operation of the sensible heat exchange rotor and the desiccant rotor, the heat disposed in the exhaust path The desiccant rotor is disposed upstream of the sensible heat exchange rotor along the flow of outside air in the air supply path, the control means is provided with a timer function, and the control means comprises: and the sensible heat exchange rotor and the desiccant rotor in operation, the desiccant rotor, a moisture absorption from outside air passing the air supply channel, by heating by said heat exchanger, In a state of releasing the serial exhaust passage, the ventilation and dehumidifying the temperature rise of suppressing the dehumidifying ventilation mode performs to room, and the operation of the sensible heat exchange rotor and the desiccant rotor stopped, the indoor When switching to a single ventilation mode for performing only ventilation, the operation of the sensible heat exchange rotor is stopped, and after a predetermined time has elapsed , the heating of the desiccant rotor by the heat exchanger and the operation of the desiccant rotor are stopped. .

A control method for a desiccant ventilation fan according to the second invention that meets the above-mentioned object is a sensible heat exchange rotor that moves heat from an air supply path that sends outside air into a room to an exhaust path that discharges air in the room, and the air supply path in the inner disposed upstream of the sensible heat exchange rotor along the external air flow, and a desiccant rotor for moving the water to the exhaust passage from the air supply passage, the control of the desiccant ventilators for ventilating the room In the method, the sensible heat exchange rotor and the desiccant rotor are operated, and the desiccant rotor is absorbed from outside air passing through the supply air path by heating the desiccant rotor by a heat exchanger disposed in the exhaust path. moisture was allowed to discharge into the exhaust passage, from suppressing state temperature rise performs ventilation and dehumidification to said chamber, the operation of the sensible heat exchange rotor and the desiccant rotor Sealed, working in switching state to ventilate only to said chamber, to stop the operation of the sensible heat exchange rotor, after a predetermined time has elapsed, the heating and the desiccant rotor of the desiccant rotor due to the heat exchanger To stop.

The control method of the desiccant ventilation fan according to the first invention and the desiccant ventilation fan according to the second invention is performed when switching from a state where ventilation and dehumidification are performed to the room and a temperature rise is suppressed to a state where only ventilation is performed for the room. Then, the sensible heat exchange rotor is stopped, and after a predetermined time has elapsed, the desiccant rotor is stopped.
Therefore, before the downstream side of the sensible heat exchange rotor in the air supply path cooled by the operation of the sensible heat exchange rotor is heated, the outside air that has not been dehumidified by the desiccant rotor is removed from the sensible heat exchange rotor in the supply path. Therefore, it is possible to prevent condensation on the downstream side of the sensible heat exchange rotor in the air supply path.

It is explanatory drawing of the desiccant ventilation fan which concerns on one embodiment of this invention. It is a block diagram which shows the connection of a control means.

Next, embodiments of the present invention will be described with reference to the accompanying drawings for understanding of the present invention.
As shown in FIGS. 1 and 2, a desiccant ventilation fan 10 according to an embodiment of the present invention transfers sensible heat from an air supply path 11 that sends outside air into the room to an exhaust path 12 that exhausts indoor air. It has an exchange rotor 13, a desiccant rotor 14 that moves moisture from the air supply path 11 to the exhaust path 12, and a control means 15 that controls the operation of the sensible heat exchange rotor 13 and the desiccant rotor 14 to ventilate the room. . Details will be described below.

As shown in FIG. 1, the desiccant ventilation fan 10 includes a housing 16 in which an air supply passage 11 for sending outside air into the room and an exhaust passage 12 for discharging indoor air to the outdoors are formed. A rotor 14 and a sensible heat exchange rotor 13 are provided.
The desiccant rotor 14 is disposed so as to straddle the air supply path 11 and the exhaust path 12, and is formed by laminating corrugated plate members, honeycomb members and the like, and has a structure through which air flowing through the air supply path 11 and the exhaust path 12 flows. ing. The surface constituent material of the desiccant rotor 14 is covered with a polymeric absorbent, or a hygroscopic material such as silica gel or zeolite.

An electric motor 17 shown in FIG. 2 is provided in the housing 16, and the desiccant rotor 14 is rotated by receiving a driving force from the electric motor 17 from the side where the relative humidity of the air supply path 11 and the exhaust path 12 is high. Move moisture to the lower side.
The moisture absorbent adhering to the surface of the desiccant rotor 14 adsorbs moisture in the air and is heated, thereby releasing the adsorbed moisture and regenerating the moisture in an adsorbable state.

As shown in FIG. 1, there are heat exchangers 18 and 19 and a fan 20 in the air supply path 11. When the fan 20 is activated, outdoor outdoor air flows into the room through the air supply path 11. The heat exchanger 18 is arranged on the upstream side of the heat exchanger 19 along the flow of outside air in the air supply path 11.
Two heat exchangers 21, 22 and a fan 23 are also arranged in the exhaust path 12. When the fan 23 is activated, indoor air is discharged to the outside via the exhaust path 12. The heat exchanger 21 is on the upstream side of the heat exchanger 22 along the air flow in the room in the exhaust passage 12.
The heat exchangers 18, 19, 21, and 22 are sequentially connected by a refrigerant circuit 24 in which the refrigerant circulates.

The refrigerant circuit 24 is provided with a compressor 26 that compresses the refrigerant, a four-way valve 27 that switches a flow direction of the refrigerant, and an expansion valve 28 that depressurizes the refrigerant. The expansion valve 28 is disposed between the heat exchangers 18 and 22.
As shown in FIG. 2, the desiccant ventilation fan 10 includes control means 15 connected to the electric motor 17, the fans 20 and 23, the compressor 26, the four-way valve 27, and the expansion valve 28, and the control means 15 includes an operation panel 29. Is connected.
The control means 15 is composed of, for example, a microcomputer, and switches the four-way valve 27 in accordance with an input operation on the operation panel 29.

When the operation panel 29 performs an operation for starting an operation of dehumidifying the room along with ventilation (hereinafter also referred to as “dehumidifying ventilation mode”), the control means 15 causes the four-way valve 27 to be discharged from the compressor 26. The refrigerant passes through the heat exchangers 21 and 22, the expansion valve 28, and the heat exchangers 18 and 19 in order to return to the compressor 26, and the compressor 26 is operated. The refrigerant in the refrigerant circuit 24 circulates in the refrigerant circuit 24 by the operation of the compressor 26.
During the dehumidification ventilation mode, the high-pressure gaseous refrigerant discharged from the compressor 26 passes through the heat exchangers 21 and 22 and condenses, and then is brought into a low-pressure state by the expansion valve 28, and the heat exchangers 18 and 19 are turned on. It passes and evaporates and returns to the compressor 26. At this time, the heat exchangers 18 and 19 act as evaporators, and the heat exchangers 21 and 22 act as condensers.

Part of the gaseous refrigerant exiting the compressor 26 becomes liquid when passing through the heat exchanger 21, and the remainder that has not become liquid in the heat exchanger 21 becomes liquid when passing through the heat exchanger 22. . The refrigerant that has become liquid as a whole is partially vaporized when passing through the heat exchanger 18, and the rest is evaporated when passing through the heat exchanger 19.

The desiccant rotor 14 absorbs moisture from the outside air passing through the air supply path 11, is heated by the heat of condensation of the heat exchanger 21, releases the absorbed moisture into the exhaust path 12, and absorbs moisture. It becomes possible. As a result, the moisture that has moved from the outside air flowing in the air supply path 11 to the desiccant rotor 14 is discharged to the outside together with the indoor air flowing in the exhaust path 12. Therefore, the room is ventilated in a state where the increase in humidity is suppressed.

On the other hand, when an operation for starting the operation of moisturizing the room together with ventilation on the operation panel 29 (hereinafter also referred to as “moisturizing ventilation mode”) is performed, the control means 15 switches the state of the four-way valve 27 to perform compression. The refrigerant discharged from the machine 26 passes through the heat exchangers 19 and 18, the expansion valve 28, and the heat exchangers 22 and 21 in order to return to the compressor 26. At this time, the heat exchangers 18 and 19 act as condensers, and the heat exchangers 21 and 22 act as evaporators.

As a result, the high-temperature and high-pressure gaseous refrigerant discharged from the compressor 26 passes through the heat exchangers 19 and 18, condenses, and is then brought to a low pressure state by the expansion valve 28 and passes through the heat exchangers 22 and 21. Then, it evaporates and returns to the compressor 26.
The desiccant rotor 14 absorbs moisture from the indoor air passing through the exhaust passage 12 and is heated by the heat exchanger 18 in the supply passage 11 to release the absorbed moisture into the supply passage 11. Therefore, the room is in a state where moisture is kept together with ventilation.

Further, the sensible heat exchange rotor 13 provided in the housing 16 is disposed across the air supply path 11 and the exhaust path 12 as shown in FIG. Similarly to the desiccant rotor 14, the sensible heat exchange rotor 13 is formed by laminating corrugated plate members, honeycomb members, and the like, and has a structure through which air flowing through the air supply path 11 and the exhaust path 12 flows.
An electric motor 30 connected to the control means 15 shown in FIG. 2 is provided in the housing 16, and the sensible heat exchange rotor 13 is rotated by driving of the electric motor 30, and the outside air and exhaust gas flowing in the air supply path 11. Heat is absorbed from the higher temperature side of the indoor air flowing through the passage 12, and is radiated to the lower temperature side.

When the sensible heat exchange rotor 13 is operated when the outdoor temperature is higher than that in the room, the sensible heat exchange rotor 13 takes heat from the outside air flowing into the room through the air supply path 11 and releases the heat to the exhaust path 12. The heat released in the exhaust path 12 is carried outdoors by indoor air flowing in the exhaust path 12. Therefore, the room is in a state in which the temperature rise is suppressed.
When the sensible heat exchanging rotor 13 operates when the outdoor temperature is lower than that in the room, the sensible heat exchanging rotor 13 takes heat from the indoor air discharged to the outside through the exhaust path 12 and releases the heat to the air supply path 11. To do. Therefore, the outside air flowing through the air supply path 11 is heated by the sensible heat exchange rotor 13 and then flows into the room, thereby suppressing the temperature in the room from decreasing.

In the present embodiment, the heat exchanger 18, the desiccant rotor 14, the sensible heat exchange rotor 13, and the heat exchanger 19 are sequentially arranged in the air supply path 11 along the flow of the outside air in the air supply path 11. A sensible heat exchange rotor 13, a heat exchanger 21, a desiccant rotor 14, and a heat exchanger 22 are arranged in this order along the flow of air in the exhaust path 12.
Therefore, when the dehumidifying ventilation mode is performed when the outdoor temperature is higher than the indoor temperature, the outside air flowing through the air supply path 11 passes through the sensible heat exchange rotor 13 and is then cooled, and then the heat exchanger 19 evaporates. It is further cooled by heat and sent to the room. When the moisture keeping ventilation mode is performed when the outdoor temperature is lower than the indoor temperature, the outside air flowing in the air supply passage 11 passes through the sensible heat exchange rotor 13 and is warmed, and then the heat exchanger 19 condenses. It is further warmed by heat and flows into the room.

As shown in FIG. 1, the air supply path 11 is provided with a temperature sensor 31 for measuring the temperature of the outside air taken into the air supply path 11 on the upstream side of the heat exchanger 18. A temperature / humidity sensor 32 for measuring the temperature and humidity of the indoor air taken into the exhaust passage 12 is provided on the upstream side of the sensible heat exchange rotor 13. The refrigerant circuit 24 is provided with a temperature sensor 33 that measures the temperature of the refrigerant circulating in the refrigerant circuit 24 between the heat exchanger 22 and the expansion valve 28.
The temperature sensor 31, the temperature / humidity sensor 32, and the temperature sensor 33 are connected to the control means 15, as shown in FIG.

In the ventilation operation by the desiccant ventilation fan 10, there is a ventilation single mode in which only ventilation is performed in the room in addition to the dehumidification ventilation mode and the moisture retention ventilation mode.
The dehumidifying ventilation mode and the moisturizing ventilation mode operate the sensible heat exchange rotor 13 and the desiccant rotor 14 together with the fans 20 and 23, while the ventilation unit mode stops the sensible heat exchange rotor 13 and the desiccant rotor 14 and the fan 20 , 23 is activated.
Since the compressor 26 is also stopped during the ventilation single mode, the refrigerant in the refrigerant circuit 24 does not circulate.

Since the sensible heat exchange rotor 13, the desiccant rotor 14 and the compressor 26 are operating during the dehumidification ventilation mode, the sensible heat exchange rotor 13, the desiccant rotor 14 and the compression are used in order to switch the dehumidification ventilation mode to the ventilation single mode. The machine 26 needs to be stopped.
Here, if the sensible heat exchange rotor 13 and the desiccant rotor 14 are stopped simultaneously from the state in which the dehumidifying ventilation mode is performed, there is a possibility that the downstream side of the sensible heat exchange rotor 13 in the air supply path 11 is condensed. This is because the outside air that has not been dehumidified by the desiccant rotor 14 is supplied to the downstream side of the sensible heat exchange rotor 13 in the air supply path 11 cooled by the outside air that has passed through the sensible heat exchange rotor 13 during the dehumidification ventilation mode. Because.

Therefore, in the present embodiment, a control method of the desiccant ventilation fan 10 that prevents condensation on the downstream side of the sensible heat exchange rotor 13 in the air supply path 11 is adopted.
The control method of the desiccant ventilation fan 10 is that the control means 15 stops the sensible heat exchange rotor 13 when switching the dehumidification ventilation mode to the ventilation single mode, and stops the desiccant rotor 14 and the compressor 26 after a predetermined time has elapsed. It is something to be made. As a result, outside air dehumidified by the desiccant rotor 14 is sent to the downstream side of the sensible heat exchange rotor 13 in the air supply path 11 after the sensible heat exchange rotor 13 is stopped. Condensation on the downstream side of the sensible heat exchange rotor 13 can be suppressed.
And while the sensible heat exchange rotor 13 is stopped and the desiccant rotor 14 is operating, the temperature of the downstream side of the sensible heat exchange rotor 13 of the air supply path 11 is increased by the outside air flowing through the air supply path 11. Thereafter, even if the desiccant rotor 14 is stopped, it is possible to prevent condensation on the downstream side of the sensible heat exchange rotor 13 in the air supply path 11.

The time until the desiccant rotor 14 is stopped after the sensible heat exchange rotor 13 is stopped (hereinafter also referred to as “transition time”) can be determined by logical examination and experimental examination. The range is 15 minutes, specifically 10 minutes.
The control means 15 has a timer function, and stops the desiccant rotor 14 and the compressor 26 when it is detected that the transition time has elapsed after the sensible heat exchange rotor 13 is stopped.

The transition time can be determined from the outdoor temperature and humidity in the season in which the dehumidification ventilation mode is performed, and the temperature on the downstream side of the sensible heat exchange rotor 13 in the air supply path 11 when the dehumidification ventilation mode is being performed.
Specifically, the dew point temperature (hereinafter referred to as “assumed dew point”) from the temperature (hereinafter also referred to as “assumed temperature”) and humidity (hereinafter also referred to as “assumed humidity”) assumed as the season (summer) in which the dehumidification ventilation mode is performed. Further, the temperature on the downstream side of the sensible heat exchange rotor 13 in the air supply path 11 when the dehumidifying ventilation mode is performed is measured at the assumed temperature and the assumed humidity. Next, the temperature on the downstream side of the sensible heat exchange rotor 13 in the air supply path 11 that changes over time with the sensible heat exchange rotor 13 stopped while the desiccant rotor 14 is operated at the assumed temperature and assumed humidity. Record. Then, the time from when the sensible heat exchange rotor 13 is stopped until the temperature on the downstream side of the sensible heat exchange rotor 13 in the air supply path 11 reaches the assumed dew point temperature + α ° C. is determined as the transition time. α ° C. is provided in the range of 3 to 8 ° C. in order to reliably prevent condensation.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and all changes in conditions and the like that do not depart from the gist are within the scope of the present invention.
For example, it is possible to provide only one heat exchanger in the air supply path and one heat exchanger in the exhaust path. Further, instead of the heat exchanger, an electric heater or other heating means may be used to heat the desiccant rotor so that moisture can be absorbed.

10: Desiccant ventilation fan, 11: Air supply path, 12: Exhaust path, 13: Sensible heat exchange rotor, 14: Desiccant rotor, 15: Control means, 16: Housing, 17: Electric motor, 18, 19: Heat exchanger, 20: fan, 21, 22: heat exchanger, 23: fan, 24: refrigerant circuit, 26: compressor, 27: four-way valve, 28: expansion valve, 29: operation panel, 30: electric motor, 31: temperature sensor 32: Temperature / humidity sensor 33: Temperature sensor

Claims (2)

A sensible heat exchange rotor that moves heat from an air supply path that sends outside air into the room to an exhaust path that exhausts the indoor air, a desiccant rotor that moves moisture from the air supply path to the exhaust path, and the sensible heat exchange A desiccant ventilation fan for ventilating the room, having a rotor and control means for controlling the operation of the desiccant rotor,
A heat exchanger disposed in the exhaust passage, wherein the desiccant rotor is disposed upstream of the sensible heat exchange rotor along the flow of outside air in the air supply passage, and the control means has a timer function The control means activates the sensible heat exchange rotor and the desiccant rotor , and the desiccant rotor heats the moisture absorbed from the outside air passing through the air supply path by the heat exchanger. From the dehumidification / ventilation mode that ventilates and dehumidifies the room and suppresses the temperature rise, the operation of the sensible heat exchange rotor and the desiccant rotor is stopped, when switching to ventilation alone mode only ventilation to the room, after the operation of the sensible heat exchange rotor is stopped, the predetermined time has elapsed, the de by the heat exchanger Desiccant ventilators, characterized in that stopping the heating and operation of the desiccant rotor Kantorota. A sensible heat exchange rotor for transferring heat from an air supply path for sending outside air into the room to an exhaust path for exhausting air in the room, and upstream of the sensible heat exchange rotor along the flow of outside air in the air supply path is disposed, and a desiccant rotor for moving the water to the exhaust passage from the air supply passage, the control method of the desiccant ventilators for ventilating the room,
The sensible heat exchange rotor and the desiccant rotor are operated, and moisture absorbed from outside air passing through the air supply path to the desiccant rotor by heating the desiccant rotor by a heat exchanger disposed in the exhaust path. From the state where it is discharged into the exhaust passage to ventilate and dehumidify the room and suppress the temperature rise, the operation of the sensible heat exchange rotor and the desiccant rotor is stopped and only the room is ventilated. When switching to a state, the operation of the sensible heat exchange rotor is stopped, and after a predetermined time has elapsed , heating of the desiccant rotor by the heat exchanger and operation of the desiccant rotor are stopped. Control method.

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