EP-4737813-A1 - AIR CONDITIONER, HEAT SOURCE MODULE, INDOOR UNIT, AND METHOD FOR CONTROLLING AIR CONDITIONER

Abstract

An air conditioning device according to an embodiment of the present invention includes: a primary refrigerant circuit, through which a primary refrigerant circulates, the primary refrigerant circuit including an outdoor unit including a compressor and an outdoor heat exchanger, and at least one relay unit including a water-refrigerant heat exchanger that exchanges heat between a refrigerant and water and connected to the outdoor unit; a secondary refrigerant circuit, through which a secondary refrigerant circulates, the secondary refrigerant circuit including at least one indoor unit connected to the water-refrigerant heat exchanger and including a water heat exchanger, and a circulation pump; and a control device that controls the compressor. The control device executes one of a room temperature control mode to control a rotation speed of the compressor on the basis of information related to an indoor load and a water temperature control mode to control the rotation speed of the compressor on the basis of information related to a heat load of the secondary refrigerant circuit.

Inventors

• Suda, Kazuki

Assignees

• Fujitsu General Limited

Dates

Publication Date

20260506

Application Date

20240627

Claims (8)

1. An air conditioning device, comprising: a primary refrigerant circuit, through which a primary refrigerant circulates, the primary refrigerant circuit including an outdoor unit including a compressor and an outdoor heat exchanger, and at least one relay unit including a water-refrigerant heat exchanger that exchanges heat between a refrigerant and water and connected to the outdoor unit; a secondary refrigerant circuit, through which a secondary refrigerant circulates, the secondary refrigerant circuit including at least one indoor unit connected to the water-refrigerant heat exchanger and including a water heat exchanger, and a circulation pump; and a control device that controls the compressor, wherein the control device executes one of a room temperature control mode to control a rotation speed of the compressor on a basis of information related to an indoor load and a water temperature control mode to control the rotation speed of the compressor on a basis of information related to a heat load of the secondary refrigerant circuit.
2. The air conditioning device according to claim 1, wherein the indoor unit further includes a room temperature sensor that detects an indoor temperature, and the control device stores a set temperature of the indoor temperature and calculates the indoor load on a basis of a difference between the indoor temperature and the set temperature.
3. The air conditioning device according to claim 1, wherein the secondary refrigerant circuit further includes a water temperature sensor that is provided on a downstream side of the water-refrigerant heat exchanger and detects a temperature of the secondary refrigerant, and the control device stores a target temperature of the secondary refrigerant and calculates the heat load on a basis of a difference between the temperature of the secondary refrigerant and the target temperature.
4. The air conditioning device according to claim 1, wherein the relay unit further includes a reception section that receives an input instruction of a user, and the control device executes the water temperature control mode, when the input instruction is received via the reception section.
5. The air conditioning device according to claim 1, wherein the secondary refrigerant circuit includes a plurality of the indoor units, and the control device executes the room temperature control mode by receiving the information related to the indoor load, the information being transmitted from the indoor units, and executes, when there is one or more of the indoor units, for which transmission of the information related to the indoor load fails to be confirmed, the water temperature control mode to control the rotation speed of the compressor on a basis of the information related to the heat load of the secondary refrigerant circuit.
6. A heat source module, comprising: a primary refrigerant circuit, through which a primary refrigerant circulates, the primary refrigerant circuit including an outdoor unit including a compressor and an outdoor heat exchanger, and at least one relay unit including a water-refrigerant heat exchanger that exchanges heat between a refrigerant and water and connected to the outdoor unit; and a control device that controls the compressor, wherein the control device executes one of a room temperature control mode to control a rotation speed of the compressor on a basis of information related to an indoor load, the information being transmitted from at least one indoor unit connected to the water-refrigerant heat exchanger and including a water heat exchanger, and a water temperature control mode to control the rotation speed of the compressor on a basis of information related to a heat load of the secondary refrigerant circuit.
7. An indoor unit that is connected to the heat source module according to claim 6 and includes a water heat exchanger connected to the water-refrigerant heat exchanger, the indoor unit comprising means for detecting the indoor load for causing the control device to execute the room temperature control mode to control the rotation speed of the compressor on a basis of the information related to the indoor load.
8. A control method for an air conditioning device that includes a primary refrigerant circuit, through which a primary refrigerant circulates, the primary refrigerant circuit including an outdoor unit including a compressor and an outdoor heat exchanger, and at least one relay unit including a water-refrigerant heat exchanger that exchanges heat between a refrigerant and water and connected to the outdoor unit; and a secondary refrigerant circuit, through which a secondary refrigerant circulates, the secondary refrigerant circuit including at least one indoor unit connected to the water-refrigerant heat exchanger and including a water heat exchanger, and a circulation pump, the control method comprising: executing, when the outdoor unit receives information related to an indoor load, the information being transmitted from the indoor unit, a room temperature control mode to control a rotation speed of the compressor on a basis of the information related to the indoor load; and executing, when transmission of the information related to the indoor load from the indoor unit fails to be confirmed, a water temperature control mode to control the rotation speed of the compressor on a basis of information related to a heat load of the secondary refrigerant circuit.

Description

Technical Field The present invention relates to an air conditioning device including a relay unit that connects a refrigerant circuit and a water circuit, a heat source module, an indoor unit, and a control method for an air conditioning device. Background Art There is known an air conditioning device including: a refrigerant circuit including a compressor that circulates a refrigerant and an outdoor heat exchanger; a water-refrigerant heat exchanger; a water circuit including a pump that circulates water for exchanging heat with the refrigerant; and a plurality of indoor units connected to the water circuit or to the water circuit and the refrigerant circuit. This type of air conditioning device is known for a method of controlling the rotation speed of the compressor on the basis of a temperature difference between a room temperature and a set temperature during heating. Citation List Patent Literature Patent Literature 1: Japanese Patent Application Laid-open No. 2003-65585 Disclosure of Invention Technical Problem However, the technology described in Patent Literature 1 assumes that the indoor unit including means for detecting an indoor load, such as a sensor that detects an indoor temperature, is connected. Hence, if an indoor unit without means for detecting an indoor load is connected or if a heating unit of a natural convection system, such as an underfloor heating unit, is connected, the above control cannot be performed. In view of the circumstances as described above, it is an object of the present invention to provide an air conditioning device, a heat source module, an indoor unit, and a control method for an air conditioning device, which are capable of performing an operation that follows an indoor load without depending on a function of an indoor unit. Solution to Problem An air conditioning device according to an embodiment of the present invention includes: a primary refrigerant circuit, through which a primary refrigerant circulates, the primary refrigerant circuit including an outdoor unit including a compressor and an outdoor heat exchanger, and at least one relay unit including a water-refrigerant heat exchanger that exchanges heat between a refrigerant and water and connected to the outdoor unit; a secondary refrigerant circuit, through which a secondary refrigerant circulates, the secondary refrigerant circuit including at least one indoor unit connected to the water-refrigerant heat exchanger and including a water heat exchanger, and a circulation pump; and a control device that controls the compressor, in which the control device executes one of a room temperature control mode to control a rotation speed of the compressor on the basis of information related to an indoor load and a water temperature control mode to control the rotation speed of the compressor on the basis of information related to a heat load of the secondary refrigerant circuit. The indoor unit may further include a room temperature sensor that detects an indoor temperature, and the control device may store a set temperature of the indoor temperature and may calculate the indoor load on the basis of a difference between the indoor temperature and the set temperature. The secondary refrigerant circuit may further include a water temperature sensor that is provided on a downstream side of the water-refrigerant heat exchanger and detects a temperature of the secondary refrigerant, and the control device may store a target temperature of the secondary refrigerant and may calculate the heat load on the basis of a difference between the temperature of the secondary refrigerant and the target temperature. The relay unit may further include a reception section that receives an input instruction of a user, and the control device may execute the water temperature control mode, when the input instruction is received via the reception section. The secondary refrigerant circuit may include a plurality of the indoor units, and the control device may execute the room temperature control mode by receiving the information related to the indoor load, the information being transmitted from the indoor units, and may execute, when there is one or more of the indoor units, for which transmission of the information related to the indoor load fails to be confirmed, the water temperature control mode to control the rotation speed of the compressor on the basis of the information related to the heat load of the secondary refrigerant circuit. A heat source module according to an embodiment of the present invention includes: a primary refrigerant circuit, through which a primary refrigerant circulates, the primary refrigerant circuit including an outdoor unit including a compressor and an outdoor heat exchanger, and at least one relay unit including a water-refrigerant heat exchanger that exchanges heat between a refrigerant and water and connected to the outdoor unit; and a control device that controls the compressor, in which the control