JP7166220B2 - ventilation air conditioning system - Google Patents

Description

The present invention relates to a ventilation and air-conditioning system that combines a ventilation device using a heat exchanger and an air-conditioning system that performs air-conditioning by flowing cold or hot water through a radiator.

Patent Literature 1 discloses a heating system that includes a ventilation section using an air heat exchanger and a circulation section that circulates hot water to a radiator. The ventilation section consists of an air heat exchanger that exchanges heat between indoor and outdoor air, a supply air path from the outdoor intake to the indoor outlet via the air heat exchanger, and an air heat exchanger from the indoor intake. and an exhaust air passage leading to an outdoor air outlet. The circulation unit includes a heat source unit that generates and delivers hot water, a first radiator that releases the heat of the hot water into the room to heat the room, and air heat exchange using the hot water that has been reduced to a low temperature by releasing heat from the first radiator. A second radiator that heats the supplied air after passing through the device, and a hot water circulation circuit that connects the heat source device, the first radiator and the second radiator and circulates hot water. In the heating system described in Patent Document 1, the air taken in from the outdoor air inlet and heat-exchanged by the air heat exchanger is further heat-exchanged by the second radiator and introduced into the room. temperature drop is prevented.

Japanese Patent No. 4419475

By the way, in general ventilation and air-conditioning systems, a heat source device capable of generating hot water and cold water, such as a heat pump type heat source device, is used. What is disclosed in Patent Document 1 is a heating system. If the heat source machine were to be subjected to cooling operation in this heating system, cold water would be supplied to the second radiator. Therefore, when the temperature of the second radiator falls below the dew point temperature of the air taken in by the supplied air, dew condensation occurs and the condensed water drips onto the ceiling or floor.

The present invention has been made in view of the above, and the air taken in by air supply is an air heat exchanger and a radiator using a cooling or heating heat medium used for indoor heat exchange. To provide a ventilation and air conditioning system capable of suppressing dew condensation on a radiator when heat is exchanged between and.

In order to solve the above-described problems and achieve the object, the ventilation and air conditioning system of the present invention includes a ventilation device, a heat source device, a first radiator, a second radiator, a three-way valve, and a dew point temperature detector. , a second radiator inlet temperature detector, a three- way valve inlet temperature detector, and a three-way valve controller. The ventilation system has an air heat exchanger that exchanges heat between outdoor air outside the building and indoor air inside the building. The heat source machine generates and delivers a heat medium. The first radiator air-conditions the inside of the building using the heat of the heat medium. The second radiator cools or heats the outdoor air after passing through the air heat exchanger using the heat of the heat medium. The three-way valve comprises a first path for circulating the heat medium between the heat source machine and the first radiator, and a first path for circulating the heat medium between the heat source machine, the first radiator, and the second radiator. switch to any one of the second routes that allow The dew point temperature detector detects the dew point temperature of the air that has passed through the air heat exchanger. The second radiator inlet temperature detection unit detects a second radiator inlet temperature, which is the temperature at the inlet of the second radiator in the second path. The three-way valve inlet temperature detector detects the three-way valve inlet temperature, which is the temperature of the inlet of the three-way valve. The three-way valve controller compares the dew point temperature with the inlet temperature of the second radiator to control switching of the three-way valve while the heat medium is circulating through the second path. The three-way valve control unit switches the path of the heat medium to the second path when the three-way valve inlet temperature is higher than the dew point temperature while the heat medium is circulating through the first path. Further, the three-way valve control unit compares the dew point temperature and the inlet temperature of the second radiator when the heat medium is circulating through the second path, and if the inlet temperature of the second radiator is lower than the dew point temperature, Then, the path of the heat medium is switched to the first path.

According to the present invention, when the air taken in by the air supply is heat-exchanged between the air heat exchanger and the radiator using the cooling or heating heat medium used for heat exchange in the room , the effect of being able to suppress dew condensation in the radiator is exhibited.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 schematically shows an example of a configuration of a ventilation air conditioning system according to an embodiment; Diagram showing an example of a psychrometric diagram The figure which shows an example of the hardware constitutions of the three-way valve control part with which the ventilation air conditioning system concerning embodiment is equipped. Flowchart showing an example of the procedure of the ventilation air-conditioning method according to the embodiment 4 is a time chart showing an example of the relationship between the temperature of the heat medium and the control of the three-way valve according to the embodiment;

BEST MODE FOR CARRYING OUT THE INVENTION A ventilation and air-conditioning system according to an embodiment of the present invention will be described in detail below with reference to the drawings. In addition, this invention is not limited by this embodiment.

Embodiment.
FIG. 1 is a schematic diagram of an example of a configuration of a ventilation and air conditioning system according to an embodiment. The ventilation air-conditioning system 10 is a system that air-conditions and ventilates the building 1 , and is installed in the building 1 . The ventilation and air conditioning system 10 includes a heat source device 11 , a first radiator 12 and a second radiator 13 .

The heat source device 11 generates a heat medium used for cooling and heating the building 1 and sends it to the first radiator 12 or the first radiator 12 and the second radiator 13 . An example of the heat source equipment 11 is a heat pump cold/hot water heat source equipment. An example of a heat carrier is cold or hot water.

The first radiator 12 air-conditions the interior of the building 1 using cold heat or warm heat of the heat medium supplied from the heat source device 11 . The second radiator 13 uses the cold or hot heat of the heat medium supplied from the first radiator 12 to cool or heat the air taken in by the supplied air passing through the air heat exchanger 33, which will be described later.

The heat source device 11 and the first radiator 12 are connected by pipes 21 and 22 . The pipe 21 is a pipe for flowing a heat medium from the heat source device 11 to the first radiator 12 . The pipe 22 is a pipe for flowing the heat medium from the first radiator 12 to the heat source device 11 . Further, the pipe 22 and the second radiator 13 are connected by pipes 23 and 24 . The pipe 23 is a pipe for flowing the heat medium from the first radiator 12 to the second radiator 13 . The pipe 24 is a pipe for flowing the heat medium from the second radiator 13 to the heat source device 11 .

A three-way valve 25 is provided at the connecting portion between the pipes 22 and 23 . The three-way valve 25 is connected to a pipe 22a connected to the first radiator 12, a pipe 23 connected to the second radiator 13, and a pipe 22b connected to the heat source device 11, so that the heat medium from the first radiator 12 is It is a valve that switches the flow path between the pipe 22b and the pipe 23. FIG. The pipe 24 is connected to pipes 22 b and 22 c connecting the heat source device 11 and the three-way valve 25 . The pipes 22 include a pipe 22a connecting between the first radiator 12 and the three-way valve 25, a pipe 22b connecting between the three-way valve 25 and the connecting portion of the pipe 24, and a connecting portion of the pipe 24 and the heat source device 11. It includes a pipe 22c connecting between.

As shown in FIG. 1, in the ventilation and air-conditioning system 10, the heat medium supplied from the heat source device 11 to the first radiator 12 passes through pipes 22a, 22b, and 22c and returns directly to the heat source device 11 on the first route. 71, and a second route 72 that passes through the pipes 22a and 23, passes through the second radiator 13, passes through the pipes 24 and 22c, and returns to the heat source device 11. That is, the first path 71 is a path for circulating the heat medium between the heat source device 11 and the first radiator 12, and the second path 72 is the heat source device 11, the first radiator 12, and the second radiator. 13 for circulating the heat medium. The three-way valve 25 switches the path through which the heat medium flows to the first path 71 or the second path 72 .

The ventilation air conditioning system 10 includes a ventilation device 30 that exchanges air between the inside and outside of the building 1 . The ventilator 30 generates an air supply flow A and an exhaust air flow B when the ventilation operation is started. In one example, the ventilation device 30 is provided in the attic of the building 1 . The ventilator 30 includes an outdoor air inlet 31 , an indoor air inlet 32 , an air heat exchanger 33 , an indoor air outlet 34 and an outdoor air outlet 35 .

The outdoor air inlet 31 takes air outside the building 1 into the ventilation device 30 . The indoor air inlet 32 takes air inside the building 1 into the ventilation device 30 . Below, the air outside the building 1 is called outdoor air, and the air inside the building 1 is called indoor air. The air heat exchanger 33 exchanges heat between outdoor air from the outdoor air inlet 31 and indoor air from the indoor air inlet 32 . The indoor air outlet 34 blows out the outdoor air that has passed through the air heat exchanger 33 into the building 1 . The outdoor air outlet 35 blows out the exhaust, which is the indoor air that has passed through the air heat exchanger 33 , to the outside of the building 1 . The outdoor air inlet 31 , the indoor air inlet 32 , the indoor outlets 34 and 35 , and the air heat exchanger 33 are connected via piping 36 .

The second radiator 13 is arranged in the air passage between the air heat exchanger 33 of the ventilation device 30 and the indoor outlet 34 .

When the ventilator 30 starts operating, an intake airflow A and an exhaust airflow B are generated. That is, the outdoor air sucked from the outdoor air inlet 31 is heat-exchanged by the air heat exchanger 33, passes through the second radiator 13, and is supplied to the inside of the building 1 from the indoor air outlet 34. Become A. Also, the indoor air sucked from the indoor air inlet 32 undergoes heat exchange in the air heat exchanger 33 and becomes an exhaust flow B that is exhausted from the outdoor air outlet 35 .

The ventilation air conditioning system 10 includes a dew point temperature detector 41 , a second radiator inlet temperature detector 42 , a three-way valve inlet temperature detector 43 , an operating state detector 44 , and a three-way valve controller 45 .

The dew point temperature detector 41 detects the dew point temperature of the air in the supply airflow A after passing through the air heat exchanger 33 . In one example, the dew point temperature detector 41 is provided in the air passage between the air heat exchanger 33 and the second radiator 13 . FIG. 2 is a diagram showing an example of a psychrometric chart. In FIG. 2, the horizontal axis indicates the dry bulb temperature and the vertical axis indicates the absolute humidity. The dew point temperature T2 is the dry-bulb temperature in the temperature and humidity state D in which the supply airflow A after passing through the air heat exchanger 33 is cooled from the temperature and humidity state C and the relative humidity becomes 100%. The temperature and humidity state C has a dry bulb temperature of T1 and a relative humidity of E%. As an example of the dew point temperature detector 41, a cooling dew point meter or a capacitance dew point meter is used.

The second radiator inlet temperature detector 42 detects the temperature at the inlet of the second radiator 13 on the second path 72 . The second radiator inlet temperature detector 42 is provided upstream of the second radiator 13 in the second path 72 . The three-way valve inlet temperature detector 43 detects the temperature at the inlet of the three-way valve 25 . The three-way valve inlet temperature detector 43 is provided in the pipe 22a that constitutes the first path 71 and the second path 72 . An example of the second radiator inlet temperature detector 42 and the three-way valve inlet temperature detector 43 is a thermistor or a bimetal thermometer.

The operating state detector 44 detects the operating state of the ventilator 30 . As an example, the operating state detection unit 44 detects that the ventilation device 30 is in the operating state when the ventilation device 30 is in the energized state, and detects that the ventilation device 30 is in the operating state when the ventilation device 30 is in the non-energized state. Suppose it is not in The detection result of the operating state of the ventilator 30 is output to the three-way valve control section 45 upon request from the three-way valve control section 45 .

The three-way valve control unit 45 controls the temperature detected by the dew point temperature detection unit 41, the second radiator inlet temperature detection unit 42, and the three-way valve inlet temperature detection unit 43 so that condensation does not occur in the second radiator 13. The switching of the three-way valve 25 is controlled as follows. Specifically, when the second radiator inlet temperature detected by the second radiator inlet temperature detector 42 is lower than or equal to the dew point temperature detected by the dew point temperature detector 41, the three-way valve controller 45 controls the second heat radiator The three-way valve 25 is switched so that the flow of water to the vessel 13 is cut off and the heat medium is circulated through the first path 71 . Further, the three-way valve control unit 45 allows water to flow to the second radiator 13 when the three-way valve inlet temperature detected by the three-way valve inlet temperature detection unit 43 is higher than the dew point temperature detected by the dew point temperature detection unit 41. and switch the three-way valve 25 to circulate the second path 72 .

The three-way valve controller 45 is implemented as a processing circuit. The processing circuit may be dedicated hardware, or may be a circuit with a processor. 3 is a diagram illustrating an example of a hardware configuration of a three-way valve control unit provided in the ventilation and air conditioning system according to the embodiment; FIG. The three-way valve control section 45 has a processor 451 and a memory 452 . Processor 451 and memory 452 are connected via bus line 453 . The three-way valve control section 45 is implemented by the processor 451 executing a program stored in the memory 452 . Also, multiple processors and multiple memories may work together to achieve the above functions. Also, part of the functions of the three-way valve control unit 45 may be implemented as an electronic circuit that is dedicated hardware, and other parts may be implemented using the processor 451 and the memory 452 .

Next, the operation of the ventilation air-conditioning system 10 having such a configuration will be described. FIG. 4 is a flow chart showing an example of the procedure of the ventilation air conditioning method according to the embodiment.

First, the operation of the heat source device 11 is started by the operation of the operation changeover switch (not shown) of the ventilation air conditioning system 10 by the user (step S11). As a result, the inside of the building 1 is air-conditioned because the heat medium, which is cold water or hot water, is supplied to the first radiator 12 .

When the operation of the heat source device 11 is started, the three-way valve 25 is switched by the three-way valve control unit 45 so that the second path 72 is closed and the first path 71 is opened (step S12). Next, it is determined whether or not the ventilator 30 is in operation by the operating state detector 44 of the ventilator 30 (step S13). If the ventilator 30 is not in operation (No in step S13), the process returns to step S12. At this time, if the three-way valve 25 has already been switched in step S12 so that the second path 72 is closed and the first path 71 is opened, that state is maintained. That is, the heat medium generated by the heat source equipment 11 continues to circulate through the first path 71 . The case where the ventilator 30 is not in operation is the case where the ventilator 30 is stopped, or the case where the ventilator 30 was in operation but stopped.

When the ventilator 30 is in operation (Yes in step S13), the three-way valve controller 45 acquires the three-way valve inlet temperature from the three-way valve inlet temperature detector 43 (step S14). Also, the three-way valve control unit 45 acquires the dew point temperature from the dew point temperature detection unit 41 (step S15). As described above, the dew point temperature T2 is obtained when the dry bulb temperature after passing through the air heat exchanger 33 is T1 and the relative humidity is 100% by cooling the supply air flow A with a relative humidity of E%. is the dry bulb temperature of Next, the three-way valve control unit 45 determines whether the three-way valve inlet temperature is higher than the dew point temperature (step S16).

If the three-way valve inlet temperature is equal to or lower than the dew point temperature (No in step S16), the process returns to step S12, and the heat medium generated by the heat source device 11 continues to circulate through the first path 71. On the other hand, when the three-way valve inlet temperature is higher than the dew point temperature (Yes in step S16), the three-way valve controller 45 opens the second path 72 and closes the first path 71. 25 is switched (step S17). As a result, the heat medium generated by the heat source device 11 passes through the second radiator 13, and the supplied air flow A from the outdoor air inlet 31 is further cooled or heated, and the temperature inside the building 1 approaches the temperature. It is blown out into the building 1. As a result, an increase in air conditioning load due to ventilation can be suppressed.

After that, the three-way valve controller 45 acquires the second radiator inlet temperature from the second radiator inlet temperature detector 42 (step S18). Also, the three-way valve control unit 45 acquires the dew point temperature from the dew point temperature detection unit 41 (step S19). Next, the three-way valve control unit 45 determines whether the inlet temperature of the second radiator is equal to or lower than the dew point temperature (step S20).

If the inlet temperature of the second radiator is higher than the dew point temperature (No in step S20), the process waits until the inlet temperature of the second radiator becomes lower than the dew point temperature. If the inlet temperature of the second radiator is equal to or lower than the dew point temperature (Yes in step S20), the process returns to step S12. That is, the three-way valve control unit 45 switches the three-way valve 25 so that the second path 72 is closed and the first path 71 is opened. Thereby, the heat medium generated by the heat source equipment 11 circulates through the first path 71 . Further, if the heat medium is circulated through the second path 72 when the inlet temperature of the second radiator is equal to or lower than the dew point temperature, condensation will occur in the second radiator 13 . However, in the present embodiment, the heat medium having a dew point temperature or lower is prevented from flowing through the second radiator 13 so that the temperature of the second radiator 13 does not drop below the dew point temperature of the supply air flow A. , condensation is prevented. Then, the processing from step S12 to step S20 is repeatedly executed.

Next, an example of control of the three-way valve 25 in the ventilation air conditioning system 10 will be described. FIG. 5 is a time chart showing an example of the relationship between the temperature of the heat medium and the control of the three-way valve according to the embodiment; Here, a curve showing an example of the temporal change of the second radiator inlet temperature Tr, a curve showing an example of the temporal change of the three-way valve inlet temperature Tt, and a time chart Ts showing an example of the switching state of the three-way valve 25 with respect to time. and shows. In FIG. 5, the horizontal axis indicates time. In the graphs showing temporal changes in the second radiator inlet temperature Tr and the three-way valve inlet temperature Tt, the vertical axis indicates the dry bulb temperature. In the time chart Ts showing the switching state of the three-way valve 25, the vertical axis shows whether the three-way valve 25 selects either the first path 71 or the second path 72. FIG.

It is assumed that the operation of the heat source device 11 is started at time t0. After time t0, the three-way valve control unit 45 switches the three-way valve 25 so that the heat medium flows through the first path 71 as shown in step S12 of FIG.

After that, it is assumed that the ventilator 30 is in operation. As shown in step S16 in FIG. 4, it is determined at time t1 whether the three-way valve inlet temperature Tt is higher than the dew point temperature T2. At time t1, the three-way valve inlet temperature Tt is higher than the dew point temperature T2. The three-way valve 25 is switched to open.

When the path of the heat medium is switched to the second path 72, as shown in step S20 of FIG. 4, the three-way valve control unit 45 determines whether the second radiator inlet temperature Tr is equal to or lower than the dew point temperature T2. . As shown in FIG. 5, the second radiator inlet temperature Tr is higher than the dew point temperature T2 until time t2, so the state of the second path 72 is maintained. Tr becomes equal to or lower than the dew point temperature T2. As a result, at time t2, the three-way valve control unit 45 switches the three-way valve 25 so that the first path 71 is opened and the second path 72 is closed, as shown in the time chart Ts. As a result, the temperature of the second radiator 13 does not fall below the dew point temperature T2 of the supply airflow A, so that dew condensation can be prevented.

After switching to the first path 71, the three-way valve control unit 45 determines whether the three-way valve inlet temperature Tt is higher than the dew point temperature T2, as shown in step S16 of FIG. As shown in FIG. 5, since the three-way valve inlet temperature Tt is equal to or lower than the dew point temperature until time t3, the state of the first path 71 is maintained. will also grow. As a result, at time t3, the three-way valve control unit 45 switches the three-way valve 25 so that the heat medium flows through the second path 72 as shown in the time chart Ts. As a result, the supply air flow A from the outdoor air inlet 31 is cooled or heated using the heat medium generated by the heat source device 11 without causing dew condensation on the second radiator 13, and is brought closer to room temperature into the building 1. blown out.

After that, the same processing is performed. That is, although the state of the second path 72 is maintained until time t4, the second radiator inlet temperature Tr becomes equal to or lower than the dew-point temperature T2 at time t4, so it is switched to the first path 71. After that, the state of the first path 71 is maintained until time t5, but is switched to the second path 72 because the three-way valve inlet temperature Tt becomes higher than the dew point temperature T2 at time t5.

Note that FIG. 1 shows a case where one first radiator 12, one second radiator 13, and one ventilation device 30 are provided for the heat source device 11, but the embodiment is not limited to this. do not have. At least one ventilation air conditioning system 10 may be provided for one heat source device 11 . Further, when a plurality of first radiators 12, second radiators 13, and ventilation devices 30 are provided, a plurality of first paths 71 and second paths 72 may be connected in parallel.

In the embodiment, the heat medium supplied from the heat source device 11 to the first radiator 12 passes through the pipes 22a, 22a, 23 and the first route 71 that returns to the heat source device 11 as it is through the pipes 22a, 22b, 22c. , a second path 72 that returns to the heat source device 11 through the pipes 24 and 22c via the second radiator 13, and a three-way valve 25 is provided. The three-way valve control unit 45 switches the three-way valve 25 so that the heat medium flows through the second path 72 when the heat medium flows through the first path 71 and the three-way valve inlet temperature is higher than the dew point temperature. . The three-way valve control unit 45 also controls the three-way valve control unit 45 so that the heat medium flows through the first path 71 when the heat medium flows through the second path 72 and the inlet temperature of the second radiator is equal to or lower than the dew point temperature. Switch valve 25 . As a result, when the ventilator 30 is in an operating state and the heat medium is caused to flow to the second radiator 13, it is possible to suppress the occurrence of dew condensation on the second radiator 13. Further, when the heat medium is flowing through the second radiator 13, the air supply flow A from the outdoor suction port 31 is cooled or heated by the heat medium. As a result, it is possible to blow out into the building 1 the supply airflow A that is close to the indoor temperature of the building 1, thereby suppressing an increase in the air conditioning load due to ventilation.

The configuration shown in the above embodiment shows an example of the content of the present invention, and it is possible to combine it with another known technology, and one configuration can be used without departing from the scope of the present invention. It is also possible to omit or change the part.

1 Building, 10 Ventilation and Air Conditioning System, 11 Heat Source Machine, 12 First Radiator, 13 Second Radiator, 21, 22, 22a, 22b, 22c, 23, 24, 36 Piping, 25 Three-Way Valve, 30 Ventilation Device, 31 Outdoor inlet 32 Indoor inlet 33 Air heat exchanger 34 Indoor outlet 35 Outdoor outlet 41 Dew point temperature detector 42 Second radiator inlet temperature detector 43 Three-way valve inlet temperature detector 44 Operating state detection unit, 45 three-way valve control unit, 71 first path, 72 second path.

Claims (6)

a ventilation system comprising an air heat exchanger for heat exchange between outdoor air outside a building and indoor air inside said building;
a heat source machine that generates and delivers a heat medium;
a first radiator that air-conditions the inside of the building using the heat of the heat medium;
a second radiator that cools or heats the outdoor air after passing through the air heat exchanger using the heat of the heat medium;
A first route for circulating the heat medium between the heat source device and the first radiator, and a first route for circulating the heat medium between the heat source device and the first radiator and the second radiator between the heat source device, the first radiator, and the second radiator. a three-way valve that switches to one of the second paths for circulating the heat medium;
a dew point temperature detection unit that detects the dew point temperature of the air that has passed through the air heat exchanger;
a second radiator inlet temperature detection unit that detects a second radiator inlet temperature that is the temperature at the inlet of the second radiator in the second path;
a three-way valve inlet temperature detection unit that detects a three-way valve inlet temperature, which is the temperature of the inlet of the three-way valve;
a three-way valve control unit that controls switching of the three-way valve;
with
The three-way valve control unit is
When the three-way valve inlet temperature is higher than the dew point temperature while the heat medium is circulating through the first path, switching the path of the heat medium to the second path,
When the heat medium is circulating through the second path, the dew point temperature is compared with the inlet temperature of the second radiator, and if the inlet temperature of the second radiator is lower than the dew point temperature, A ventilation and air-conditioning system , wherein the path of the heat medium is switched to the first path . further comprising an indoor air outlet for blowing out the outdoor air that has passed through the air heat exchanger into the interior of the building;
2. The ventilation and air-conditioning system according to claim 1 , wherein said second radiator is provided in an air passage between said air heat exchanger and said indoor outlet. The dew point temperature detection unit is provided in an air passage between the air heat exchanger and the second radiator,
3. The ventilation and air-conditioning system according to claim 1, wherein said second radiator inlet temperature detector is provided in said second path between said three-way valve and said second radiator. 4. Any one of claims 1 to 3, wherein the three-way valve inlet temperature detector is provided in the first path and the second path between the first radiator and the three-way valve. A ventilation and air conditioning system as described in . further comprising an operation detection unit that detects the operation state of the ventilation device,
5. The ventilation and air-conditioning system according to claim 1, wherein the three -way valve control unit switches the three-way valve when the ventilator is in operation. 6. The ventilation and air-conditioning system according to claim 5 , wherein the three-way valve control unit switches the path of the heat medium to the first path when the ventilation device stops operating.

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