WO2025203473A1 - Ventilation control interface device - Google Patents

Abstract

A ventilation control interface device (104) comprises: a control unit (105) that is connected to a remote controller communication line (205) that connects an indoor unit (102) of an air conditioning device and a remote controller (101) of the air conditioning device, and that controls a first ventilation device (109) and a second ventilation device (112) that perform ventilation by exhausting indoor air to the outside and supplying outside air indoors; and a remote controller communication circuit (103) that transmits and receives a signal between the control unit (105) and the remote controller (101) via the remote controller communication line (205).

Description

Ventilation Control Interface Device

This disclosure relates to a ventilation control interface device that operates an air conditioning system and ventilation equipment in conjunction with each other.

When both an air conditioning unit and a ventilation device are installed in a space to be air-conditioned, air conditioning efficiency can be improved by operating the air conditioning unit and the ventilation device in conjunction with each other. Patent Document 1 discloses a heat exchange ventilation device that includes a control unit connected to the air conditioning unit. The heat exchange ventilation device disclosed in Patent Document 1 controls the blower based on a signal input from the air conditioning unit, making it possible to operate the air conditioning unit and the ventilation device in conjunction with each other.

Japanese Patent Application Publication No. 6-281228

When operating an air conditioner and ventilation equipment in conjunction with each other, it is necessary to set operating conditions for both the air conditioner and the ventilation equipment. However, the heat exchange ventilation equipment disclosed in Patent Document 1 cannot share a remote controller with the air conditioner, so the user must set the operating conditions for the heat exchange ventilation equipment and the air conditioner in separate locations.

When operating air conditioning equipment and ventilation equipment in conjunction with each other, a centralized control system is sometimes used, in which a ventilation control interface device is connected between the air conditioning indoor unit and the ventilation equipment, and the ventilation equipment's operation settings are controlled from the air conditioning equipment's remote controller. However, when using a centralized control system, both the air conditioning indoor unit and the multiple ventilation equipment connected to the ventilation control interface device must be compatible with the centralized control system.

The present disclosure has been made in light of the above, and aims to provide a ventilation control interface device that can operate the indoor units and ventilation equipment of an air conditioning system that does not support a centralized control system in conjunction with each other, and that can set the operating conditions of each of the indoor units and ventilation equipment from a common remote controller.

In order to solve the above-mentioned problems and achieve the objectives, the ventilation control interface device according to the present disclosure is connected to a remote controller communication line that connects the indoor unit of an air conditioner with a remote controller for the air conditioner. The ventilation control interface device includes a control unit that controls at least one ventilation device that exhausts indoor air to the outdoors and supplies outside air into the indoors to perform ventilation, and a communication circuit that sends and receives signals between the control unit and the remote controller via the remote controller communication line.

The ventilation control interface device disclosed herein can operate the indoor units and ventilation equipment of an air conditioning system that does not support a centralized control system in a linked manner, and has the advantage of allowing the operating conditions of each of the indoor units and ventilation equipment to be set from a common remote controller.

FIG. 1 is a diagram showing a connection configuration of a ventilation control interface device according to a first embodiment. FIG. 1 is a diagram showing the configuration of a ventilation control interface device according to a first embodiment. FIG. 1 is a diagram showing a connection configuration of an indoor unit, a first ventilation device, and a damper, which are controlled by the ventilation control interface device according to the first embodiment. FIG. 1 is a diagram showing the configuration of a remote controller communication circuit of a ventilation control interface device according to a first embodiment. FIG. 10 is a diagram showing waveforms of signals transmitted to a remote controller of the ventilation control interface device according to the first embodiment. FIG. 10 is a diagram showing waveforms of signals received from a remote controller of the ventilation control interface device according to the first embodiment. FIG. 1 is a diagram showing the configuration of a transmission signal isolation circuit and a reception signal isolation circuit of a ventilation control interface device according to a first embodiment. FIG. 1 is a diagram showing an example of a hardware configuration that realizes a control unit included in a ventilation control interface device according to a first embodiment.

The ventilation control interface device according to the embodiment will be described in detail below with reference to the drawings.

Embodiment 1.
1 is a diagram showing a connection configuration of a ventilation control interface device according to Embodiment 1. The ventilation control interface device 104 is connected to a remote controller communication line 205 that connects an indoor unit 102 of an air conditioning apparatus 20 and a remote controller 101. Therefore, the remote controller 101 can communicate with both the indoor unit 102 and the ventilation control interface device 104.

Air conditioners 20 come in three types: one that receives power at the outdoor unit 201, one that receives power at the indoor unit 102, and one that receives power at both the outdoor unit 201 and the indoor unit 102. For air conditioners 20 known as package air conditioners that condition an entire house or office, the type that receives power at the outdoor unit 201 is the mainstream. Here, we will explain an example of an air conditioner 20 that receives power at the outdoor unit 201, where power supply voltage differences and earth impedance differences are likely to occur. However, the air conditioner 20 may also receive power at the indoor unit 102, or separately at both the outdoor unit 201 and the indoor unit 102.

The outdoor unit 201 is supplied with commercial power and is connected to earth via an earth connection terminal 202. The outdoor unit 201 and the indoor unit 102 are connected by refrigerant piping (not shown) and an internal/external connection line 203. The internal/external connection line 203 connects the power supply and earth potential between the outdoor unit 201 and the indoor unit 102.

The indoor unit 102 is connected to the remote controller 101 via a remote controller communication line 205. The ventilation control interface device 104 is also connected to the remote controller communication line 205, allowing the remote controller 101 to communicate with both the indoor unit 102 and the ventilation control interface device 104. The remote controller 101 is also equipped with a display device (not shown) and is able to display information obtained from the ventilation control interface device 104. The indoor unit 102 supplies power to part of the ventilation control interface device 104 and the remote controller 101 via the remote controller communication line 205. The power supply from the indoor unit 102 to the ventilation control interface device 104 will be described later.

The ventilation control interface device 104 is also supplied with commercial power and is connected to earth via the earth connection terminal 208.

Figure 2 is a diagram showing the configuration of the ventilation control interface device pertaining to embodiment 1. The ventilation control interface device 104 includes a remote controller communication circuit 103 that communicates with the remote controller 101, a communication terminal block 123, a power terminal block 106, a terminal block 108 to which the first ventilation device 109 is connected, a first switching circuit 110 that controls the fan speed of the first ventilation device 109 and whether or not heat exchange is performed, a terminal block 111 to which the second ventilation device 112 is connected, a second switching circuit 113 that controls the fan speed of the second ventilation device 112 and whether or not heat exchange is performed, a terminal block 114 to which the ventilation assistance device 115 is connected, a ventilation assistance device switching circuit 116 that switches the fan speed of the ventilation assistance device 115, a terminal block 117 to which dampers 118 provided for each ventilation target area are connected, and a damper opening switching circuit 119 that controls the opening and closing of the dampers 118. The ventilation control interface device 104 also includes a control unit 105 that controls the remote controller communication circuit 103, the first switching circuit 110, the second switching circuit 113, the ventilation assist device switching circuit 116, and the damper opening switching circuit 119. Based on signals received from the remote controller 101, the control unit 105 controls the first ventilation device 109 and the second ventilation device 112 to switch between operation stop and operation, switch the airflow volume, and switch whether or not to perform heat exchange ventilation. The ventilation control interface device 104 also includes a sensor circuit 120 that acquires measurements from air quality sensors 121 provided in each ventilation target area. Examples of the air quality sensors 121 include temperature sensors, humidity sensors, and carbon dioxide sensors, but other sensors may also be used. The air quality sensor 121 may also be a combination of multiple different types of sensors. In this embodiment, the air quality sensor 121 is a temperature sensor.

A remote controller communication line 205 is connected to the remote controller communication circuit 103 via the communication terminal block 123. The remote controller communication circuit 103 is a communication circuit that transmits and receives signals between the control unit 105 and the remote controller 101 via the remote controller communication line 205.

AC power is input to the power supply terminal block 106 from the external power supply 107. The power supply circuit 122 converts the AC power supplied from the external power supply 107 into DC power and supplies it to part of the ventilation control interface device 104. Note that the power lines connecting the power supply circuit 122 and part of the ventilation control interface device 104 are not shown in the figure.

The first switching circuit 110 changes the fan speed of the first ventilation device 109 and adjusts the air volume by switching the on/off of the AC signal output to the first ventilation device 109 via the terminal block 108 using a relay, semiconductor element, or the like. Note that the first switching circuit 110 may communicate with the first ventilation device 109 to have a controller (not shown) included in the first ventilation device 109 change the fan speed of the first ventilation device 109 and adjust the air volume. Furthermore, if the first ventilation device 109 is a ventilation device capable of heat exchange ventilation, the first switching circuit 110 can switch between normal ventilation and heat exchange ventilation.

The second ventilation device 112 has a different power supply system from the first ventilation device 109 and can operate at a different fan speed from the first ventilation device 109. The second switching circuit 113 changes the fan speed of the second ventilation device 112 and adjusts the air volume by switching the AC signal output to the second ventilation device 112 on and off using a relay, semiconductor element, or the like via the terminal block 111. Note that the second switching circuit 113 may communicate with the second ventilation device 112 to have a control unit (not shown) change the fan speed of the second ventilation device 112 and adjust the air volume. Furthermore, if the second ventilation device 112 is a ventilation device capable of heat exchange ventilation, the second switching circuit 113 can switch between normal ventilation and heat exchange ventilation.

Ventilation auxiliary equipment 115 is an air blower used as a circulation fan or a 24-hour ventilation fan. However, ventilation auxiliary equipment 115 may also be a circulator that blows warm air stagnating at high altitudes in a space downward to reduce temperature differences within the space. Ventilation auxiliary equipment switching circuit 116 changes the fan speed of ventilation auxiliary equipment 115 and adjusts the air volume by switching the AC signal output to ventilation auxiliary equipment 115 on and off via terminal block 114 using a relay or semiconductor element, etc.

Damper 118 is used when first ventilation equipment 109 or second ventilation equipment 112 ventilates the ventilation target area through a duct, and is installed in the duct leading to each ventilation target area. When damper 118 is driven by an AC motor, the amount of air sent to each ventilation target area can be adjusted for each ventilation target area by using a mechanism that adjusts the duct opening by the motor driving time after fully closing damper 118. When air conditioning outside air blown out from first ventilation equipment 109 or second ventilation equipment 112 to indoor unit 102, control unit 105 controls the opening of damper 118, which is installed in the air path of the air conditioned by indoor unit 102, based on a signal received from remote controller 101.

Because power is supplied to both the outdoor unit 201 and the ventilation control interface device 104 from the external power supply 107, there is a possibility that a potential difference may occur between the earth connection terminal 202 of the outdoor unit 201 and the earth connection terminal 208 of the ventilation control interface device 104 due to differences in grounding locations and power supply systems. For this reason, the ventilation control interface device 104 is insulated by an isolation circuit 209 in the remote controller communication circuit 103. By isolating the remote controller communication circuit 103, communication line communication abnormalities and component failures caused by the potential difference between the earth connection terminal 202 of the outdoor unit 201 and the earth connection terminal 208 of the ventilation control interface device 104 are avoided.

Figure 3 is a diagram showing the connection configuration of the indoor unit, first ventilation device, and damper, which are the control targets of the ventilation control interface device in embodiment 1. The ventilation control interface device 104 is not shown in Figure 3. The indoor unit 102 and first ventilation device 109 are connected by a duct 302 that sends air. The indoor unit 102 is connected to an indoor unit indoor air intake 308 that draws in indoor air. The first ventilation device 109 is connected to a ventilation device indoor air intake 307. Note that the indoor unit 102 and first ventilation device 109 may draw indoor air through a common air intake.

The first ventilation device 109 is equipped with a heat exchanger 306. The first ventilation device 109 is provided with a bypass air duct that allows air to be drawn in and exhausted outdoors without passing through the heat exchanger 306 inside or outside the first ventilation device 109, and a switching device 304 can be used to switch between ventilating through the heat exchanger 306 or through the bypass air duct.

The first ventilation device 109 is connected to the outdoor intake and exhaust vent 305 and can take in and exhaust air. The heat exchanger 306 has advantages when used to maintain temperature, but during intermediate periods and when the air conditioning unit is not in use, it may be possible to maintain the indoor temperature at an appropriate level by taking in outside air.

The switching device 304 can be controlled from the remote controller 101, and by operating the remote controller 101, it is possible to switch between ventilating through the heat exchanger 306 or through the bypass air duct.

The indoor unit 102 is provided with an air outlet 309. A duct connected to the air outlet 309 branches off and leads to a room exhaust outlet 311 and a room exhaust outlet 313. The duct leading to the room exhaust outlet 311 is provided with a damper 310 that switches the amount of air sent to the room exhaust outlet 311. In addition, the duct leading to the room exhaust outlet 313 is provided with a damper 312 that switches the amount of air sent to the room exhaust outlet 313.

An air quality sensor 121, as shown in Figure 2, is installed in each room equipped with a room exhaust vent 311, 313. The ventilation control interface device 104 adjusts the opening and opening/closing times of the dampers 310, 312 based on the measurement results of the air quality sensor 121.

Note that while the example given here is one in which the two rooms in which the room exhaust vents 311, 313 are installed are the ventilation target areas, the number of ventilation target areas may be one, or three or more. Whether the ventilation target area is one, three, or more, the damper 118 is installed corresponding to the ventilation target area.

Figure 4 is a diagram showing the configuration of the remote controller communication circuit of the ventilation control interface device according to embodiment 1. The DC voltage conversion circuit 404 converts the DC voltage input from the indoor unit 102 and generates power for use in the circuitry of the ventilation control interface device 104 that is closer to the remote controller 101 than the isolation circuit 209.

The signal used for communication between the ventilation control interface device 104 and the remote controller 101 is a type in which a signal component is superimposed on a DC voltage, and transmission and reception signals are generated and received by separating the communication signal using a transformer 405.

Figure 5 shows the waveform of a signal transmitted to the remote controller of the ventilation control interface device of embodiment 1. In the case of a circuit that performs amplitude shift keying communication, a carrier wave with a frequency of 10 kHz to 1000 kHz is generated for the transmission signal. The carrier wave is a pulse that alternates between the power supply voltage and 0 V at a constant frequency. As shown in Figure 5, the control unit 105 outputs multiple pulses at the same cycle as the carrier wave frequency. The pulses output by the control unit 105 are isolated by a photocoupler or the like in the transmission signal isolation circuit 415, but the pulse waveform is transmitted to the sine wave generation circuit 417 unchanged. The pulses input to the sine wave generation circuit 417 are shaped into a waveform close to a sine wave without changing the frequency. The pulses shaped by the sine wave generation circuit 417 are superimposed on a DC voltage by the transformer 405 to generate a transmission signal. The transmission signal is transmitted to the remote controller 101 via the remote controller communication line 205.

Figure 6 is a diagram showing the waveform of a signal received from the remote controller of the ventilation control interface device according to embodiment 1. The received signal received from the remote controller 101 has its AC signal components extracted by the transformer 405, and then its impedance is adjusted by the receiving impedance adjustment circuit 406 to adjust the voltage to fall within the power supply voltage. The received signal after impedance adjustment contains a portion that does not contain a carrier wave. The impedance-adjusted received signal has only a certain frequency extracted by the bandpass filter 408, and the waveform is converted so that it becomes high level at the carrier wave frequency. The received signal after passing through the bandpass filter 408 is isolated by a photocoupler or the like in the received signal isolation circuit 410, but the pulse waveform is sent to the control unit 105 unchanged.

Figure 7 shows the configuration of the transmit signal isolation circuit and receive signal isolation circuit of the ventilation control interface device according to embodiment 1. The transmit signal isolation circuit 415 on the transmitting side switches the carrier signal output from the transmit port 606 of the control unit 105. The high-speed photocoupler 604 is driven by passing a current amplified by the first transistor 605 through the high-speed photocoupler 604. The output of the high-speed photocoupler 604 is logically converted by the second transistor 602 and the third transistor 603, adjusting the on/off times of the waveform distorted by the high-speed photocoupler 604 and shaping the waveform. The on/off times of the waveform can be shaped by increasing the base resistance of the second transistor 602 and making the resistance between the base and collector lower than the base resistance. A transmit signal with a waveform close to a sine wave is generated by the sine wave generation circuit 417 based on the signal whose waveform has been shaped by the second transistor 602 and the third transistor 603.

The receiving signal isolation circuit 410 on the receiving side does not perform high-speed switching operations because the bandpass filter 408 shapes the carrier wave portion to a high level. For this reason, it is turned on and off using a normal photocoupler 608. The signal output from the bandpass filter 408 is input to the photocoupler 608 via a fourth P-channel transistor 609, driving the photocoupler 608. The signal output from the photocoupler 608 is input to the control unit 105 from the receiving port 607 of the control unit 105.

The transmission signal isolation circuit 415 and reception signal isolation circuit 410 can be omitted if isolation is not required. A ventilation control interface device 104 equipped with the transmission signal isolation circuit 415 and reception signal isolation circuit 410 and a ventilation control interface device 104 omitting the transmission signal isolation circuit 415 and reception signal isolation circuit 410 can share the same circuit configuration for parts other than the transmission signal isolation circuit 415 and reception signal isolation circuit 410. Therefore, even if the transmission signal isolation circuit 415 and reception signal isolation circuit 410 are omitted, the ventilation control interface device 104 can be configured without changing the software of the control unit 105.

The remote controller 101 is not only capable of setting the temperature of the air conditioning unit and switching between heating and cooling, but is also capable of operating the first ventilation device 109, the second ventilation device 112, the ventilation auxiliary device 115, and the damper 118. When the fan speed setting operation for the first ventilation device 109, the second ventilation device 112, or the ventilation auxiliary device 115 is performed from the remote controller 101, the remote controller 101 outputs a communication signal to the remote controller communication line 205 and conveys the fan speed of the first ventilation device 109, the second ventilation device 112, or the ventilation auxiliary device 115 to the ventilation control interface device 104. When the ventilation control interface device 104 receives the fan speed information, the control unit 105 controls the first switching circuit 110, the second switching circuit 113, or the ventilation auxiliary device switching circuit 116 to change the fan speed. Switching between the heat exchanger 306 and direct outside air intake, turning 24-hour ventilation on and off, and opening and closing the damper 118 can also be performed by operating the remote controller 101 using similar processing.

The outdoor unit 201 of the air conditioner is equipped with an outdoor air temperature sensor 201a, and some models are capable of measuring the outdoor air temperature. If the outdoor unit 201 is capable of measuring the outdoor air temperature, when taking in outdoor air, the outdoor unit 201 compares the outdoor air temperature measured by the outdoor air temperature sensor 201a with the temperature of the air drawn in from the indoor unit indoor air intake 308 measured by the air quality sensor 121, which is a temperature sensor. In the case of cooling, if the outdoor air temperature is lower than the indoor air temperature, control can be performed to take in outdoor air. In addition, the temperature of each room beyond the damper 118 can be measured by the air quality sensor 121, and the temperature of each room can be adjusted by heating or cooling using the air conditioner while taking in outdoor air to reach the target temperature. The control unit 105 displays the operating status of the first ventilation device 109, the second ventilation device 112, the ventilation auxiliary device 115, and the indoor unit 102 on the remote controller 101. The control unit 105 also causes the remote controller 101 to display the outside air temperature measured by the outside air temperature sensor 201a.

Furthermore, if the ventilation assistance equipment 115 is a circulator that circulates air within a building across multiple floors, and temperature sensors that serve as air quality sensors 121 are installed in rooms on each floor, the ventilation assistance equipment 115 can be operated based on the measurement values of the air quality sensors 121 in each room and the target temperature, thereby controlling the target temperatures between rooms to approach each other. If the ventilation assistance equipment 115 is a 24-hour ventilation device, it may not necessarily need to be operated when the ventilation function of the first ventilation equipment 109 or the second ventilation equipment 112 is on. For this reason, linked control may be performed to stop the ventilation assistance equipment 115 when the ventilation function of the first ventilation equipment 109 or the second ventilation equipment 112 is on.

The ventilation control interface device 104 according to embodiment 1 includes a control unit 105 that controls the ventilation equipment, and is connected to a remote controller communication line 205 that connects the remote controller 101 and the indoor unit 102. Therefore, the ventilation control interface device 104 according to embodiment 1 can perform linked operation even if the indoor unit 102, first ventilation equipment 109, and second ventilation equipment 112 do not support the centralized control method.

Furthermore, because the ventilation control interface device 104 according to embodiment 1 is connected to the remote controller communication line 205, the remote controller 101 can be shared by the indoor unit 102, the first ventilation device 109, and the second ventilation device 112. Therefore, a user of the ventilation control interface device 104 can use the remote controller 101 to set the operating conditions of the indoor unit 102, the first ventilation device 109, and the second ventilation device 112 by operating the remote controller 101.

Furthermore, the ventilation control interface device 104 according to embodiment 1 is capable of connecting and controlling the ventilation auxiliary equipment 115, and therefore, by operating the ventilation auxiliary equipment 115 in conjunction with the indoor unit 102, first ventilation equipment 109, and second ventilation equipment 112, it is possible to further improve air conditioning efficiency.

Next, the hardware configuration of the control unit 105 provided in the ventilation control interface device 104 will be described. Figure 8 is a diagram showing an example of the hardware configuration realizing the control unit provided in the ventilation control interface device according to embodiment 1. The control unit 105 is realized as a computer system using a processing circuit including a processor 91 that executes various processes, a memory 92 that serves as main memory, and a storage device 93 that stores information.

The processor 91 may be a computing device such as an arithmetic unit, microprocessor, microcomputer, CPU (Central Processing Unit), or DSP (Digital Signal Processor). The memory 92 may be a non-volatile or volatile semiconductor memory such as RAM (Random Access Memory), ROM (Read Only Memory), flash memory, EPROM (Erasable Programmable Read Only Memory), or EEPROM (Electrically Erasable Programmable Read Only Memory). The storage device 93 stores programs for executing the operation settings of the first ventilation device 109, the second ventilation device 112, the ventilation auxiliary device 115, and the indoor unit 102. The processor 91 reads the programs stored in the storage device 93 into the memory 92 and executes them. The processor 91 reads the programs stored in the storage device 93 into the memory 92 and executes them, thereby realizing the functions of the control unit 105.

The configurations shown in the above embodiments are merely examples of the content, and may be combined with other known technologies, and parts of the configuration may be omitted or modified without departing from the spirit of the invention.

20 Air conditioning device, 91 Processor, 92 Memory, 93 Storage device, 101 Remote controller, 102 Indoor unit, 103 Remote controller communication circuit, 104 Ventilation control interface device, 105 Control unit, 106 Power supply terminal block, 107 External power supply, 108, 111, 114, 117 Terminal block, 109 First ventilation device, 110 First switching circuit, 112 Second ventilation device, 113 Second switching circuit, 115 Ventilation auxiliary device, 116 Ventilation auxiliary device switching circuit, 118, 310, 312 Damper, 119 Damper opening switching circuit, 120 Sensor circuit, 121 Air quality sensor, 122 Power supply circuit, 123 Communication terminal block, 201 Outdoor unit, 201a Outdoor air temperature sensor, 202, 208 Air connection terminal, 203 internal/external connection line, 205 remote controller communication line, 209 isolation circuit, 302 duct, 304 switching device, 305 intake/exhaust port, 306 heat exchanger, 307 ventilation equipment indoor air intake, 308 indoor unit indoor air intake, 309 air outlet, 311, 313 room exhaust port, 404 DC voltage conversion circuit, 405 transformer, 406 receiving impedance adjustment circuit, 408 bandpass filter, 410 receiving signal isolation circuit, 415 transmitting signal isolation circuit, 417 sine wave generation circuit, 602 second transistor, 603 third transistor, 604 high-speed photocoupler, 605 first transistor, 606 transmitting port, 607 receiving port, 608 photocoupler, 609 fourth transistor.

Claims (11)

connected to a remote controller communication line that connects an indoor unit of an air conditioner and a remote controller of the air conditioner;
A ventilation control interface device comprising: a control unit that controls at least one ventilation device that exhausts indoor air to the outdoors and supplies outside air to the indoors to perform ventilation; and a communication circuit that transmits and receives signals between the control unit and the remote controller via the remote controller communication line. The ventilation control interface device of claim 1, wherein the control unit causes the ventilation equipment to switch between operation and stop, switch the airflow volume, and switch whether or not to perform heat exchange ventilation, based on the signal received from the remote controller. The ventilation control interface device of claim 1 or 2, wherein, when the control unit conditions the outside air blown out from the ventilation equipment to the indoor unit, the control unit controls the opening degree of a damper installed in the air path of the air conditioned by the indoor unit based on the signal received from the remote controller. The damper is driven by an AC motor;
The ventilation control interface device according to claim 3 , wherein the control unit controls the opening degree of the damper based on the driving time of the AC motor from the fully closed state of the damper. The ventilation control interface device of any one of claims 1 to 4, wherein the communication circuit includes an isolation circuit that transmits the signal while electrically insulating the remote controller communication line from the control unit. the communication circuit includes a sine wave generating circuit that makes the pulse output by the control unit closer to a sine wave, and a band pass filter that shapes the signal received from the remote controller into a pulse in which a portion including a carrier wave is at a high level and a portion not including the carrier wave is at a low level;
6. The ventilation control interface device of claim 5, wherein the isolation circuit includes a transmission signal isolation circuit provided between the sine wave generating circuit and the control unit, and a reception signal isolation circuit provided between the bandpass filter and the control unit. The ventilation control interface device of claim 6, wherein the transmission signal isolation circuit comprises a first transistor that amplifies the current of the pulse output by the control unit, a high-speed photocoupler driven by the pulse whose current is amplified in the first transistor, and a second transistor and a third transistor that shape the pulse output from the high-speed photocoupler. The ventilation control interface device of claim 3, wherein the control unit causes the indoor unit to blow out the outside air when the outdoor air temperature measured by an outdoor air temperature sensor provided in the outdoor unit of the air conditioner during cooling operation of the air conditioner is lower than the indoor temperature measured by a temperature sensor that measures the indoor temperature. A temperature sensor is installed in each room on a plurality of floors of a building to measure the temperature in the room, and a circulator is connected to the temperature sensor to circulate the air in the building across the plurality of floors,
The ventilation control interface device according to claim 3 , wherein the control unit controls the circulator based on the measurement result of the temperature sensor so that the temperature of each room on the plurality of floors approaches a target value. A 24-hour ventilation system is connected.
The ventilation control interface device according to claim 3 , wherein the control unit stops the 24-hour ventilation device when the outdoor air taken in through the outdoor air intake port is air-conditioned in the indoor unit. The ventilation control interface device of any one of claims 1 to 10, wherein the control unit causes the remote controller to display the operating status of the ventilation equipment and the indoor unit.