JP-2026075369-A - Heat source system

JP2026075369AJP 2026075369 AJP2026075369 AJP 2026075369AJP-2026075369-A

Abstract

[Problem] In a heat source system equipped with an air-cooled electric heat pump and a gas-type heat source in a circulating supply path, the objective is to appropriately respond to peak loads while preventing the electric heat pump from having to perform defrost operation, thereby suppressing a decrease in overall system efficiency and the inability to meet the desired heating load. [Solution] The circulation supply path 3, which circulates and supplies the heat transfer medium cooled or heated by the heat source unit 1 to the heat demand unit 2, is equipped with an air-cooled electric heat pump heat source unit 11 and a gas-type heat source unit 12 as the heat source unit 1. The circulation supply path 3 is equipped with a flow state switching unit 5 that switches the flow state of the heat transfer medium between a parallel state in which the heat transfer medium is circulated in parallel by branching to the electric heat pump heat source unit 11 and the gas-type heat source unit 12, and a series state in which the heat transfer medium is circulated in series in the order of electric heat pump heat source unit 11 and gas-type heat source unit 12. [Selection Diagram] Figure 2

Inventors

安江楽人
小林佑輔

Assignees

株式会社竹中工務店

Dates

Publication Date: 20260508
Application Date: 20241022

Claims (3)

A circulation supply path is provided for circulating and supplying the heat transfer medium cooled or heated by the heat source unit to the heat demand unit. The heat source system includes, as the heat source equipment, an air-cooled electric heat pump type heat source equipment and a gas type heat source equipment, in the aforementioned circulation supply path. A heat source system equipped with a flow state switching unit that switches the flow state of the heat transfer medium in the circulating supply path between a parallel state in which the heat transfer medium is passed in parallel by branching to the electric heat pump type heat source unit and the gas type heat source unit, and a series state in which the heat transfer medium is passed in series in the order of the electric heat pump type heat source unit and the gas type heat source unit.
The system includes a flow state switching control unit that controls the operating state of the flow state switching unit, The heat source system according to claim 1, wherein the flow state switching control unit operates the flow state switching unit to switch the circulation supply path to the series state when predetermined defrost operation suppression conditions are met, and switches the circulation supply path between the parallel state and the series state based on conditions other than the defrost operation suppression conditions when the defrost operation suppression conditions are not met.
The heat source unit outlet temperature setting unit sets the target outlet temperature of the electric heat pump type heat source unit, The system includes a heat source control unit that controls the operating state of the electric heat pump type heat source unit based on a target outlet temperature set in the heat source unit outlet temperature setting unit, The heat source system according to claim 1 or 2, wherein the heat source outlet temperature setting unit sets the target outlet temperature of the electric heat pump type heat source to a different temperature depending on whether the flow state switching unit switches the circulation supply path to the series state or the flow state switching unit switches the circulation supply path to the parallel state.

Description

This invention relates to a heat source system equipped with a circulation supply path for circulating and supplying a heat transfer medium cooled or heated by a heat source unit to a heat demand unit. In recent years, there has been an increasing trend towards adopting highly efficient electric heat pumps as heat sources. However, if electric heat pumps are the only heat sources provided in the circulation supply path of the above-mentioned heat source system, there is a risk that the heat load of the heat demand section may not be met during periods of tight electricity supply and demand. Therefore, as shown in Patent Document 1, a heat source system has been proposed in which an electric heat pump type heat source (electric heat source 100) and a gas type heat source (200) are provided in the circulation supply line as heat source equipment. In such a heat source system, the heat load of the heat demand section can be covered even when the power supply and demand is tight by mainly operating the gas type heat source. In the heat source system described in Patent Document 1, a heat transfer medium is passed in parallel between an electric heat pump heat source and a gas heat source in the circulation supply path. Therefore, at peak load, for example, the electric heat pump heat source and the gas heat source can be operated at full load (maximum output) to appropriately respond to the peak load. Patent No. 6912402 Configuration diagram of a heat source system showing a parallel stateDiagram showing the configuration of a heat source system in series. Embodiments of the heat source system of the present invention will be described with reference to the drawings. As shown in Figures 1 and 2, the heat source system includes a heat source unit 1, a circulation supply path 3 that circulates and supplies the heat transfer medium cooled or heated by the heat source unit 1 to the heat demand unit 2, and a control device 4 that controls the operation of each part of the heat source system. In this heat source system, the heat source unit 1 includes an air-cooled electric heat pump type heat source unit 11 and a gas type heat source unit 12. The heat demand unit 2 can be, for example, an air conditioning device that air-conditions the room by exchanging heat between the heat transfer medium cooled or heated by the heat source unit 1 and the indoor air. Although not shown in the figures, the heat demand unit 2 can include, for example, multiple air conditioning devices arranged in parallel in the circulation supply path 3. Incidentally, Figures 1 and 2 differ only in the flow state of the heat transfer medium in the circulation supply path 3, and the parts through which the heat transfer medium flows are indicated by thick lines. Also, in the flow path switching valve 51 and the flow path on/off valve 52, the open state is shown in white, and the closed state is shown in black. The electric heat pump heat source unit 11 is a heat source unit, often abbreviated as EHP, that cools or heats the heat transfer medium supplied from the circulation supply line 3 by driving the compressor of the heat pump circuit with an electric motor. In this example, the electric heat pump heat source unit 11 is shown as a pump-integrated type with a built-in pump for circulating the heat transfer medium in the circulation supply line 3. However, it is also possible to omit the built-in pump and instead place a separate primary pump in the circulation supply line 3. The heat pump circuit, although not shown in the diagram, consists of a compressor for compressing the refrigerant, an expansion valve for expanding the refrigerant, a heat exchanger on the heat transfer medium side for heating or cooling the heat transfer medium using the heat of condensation or evaporation of the refrigerant, an outside air side heat exchanger for evaporating or condensing the refrigerant in a manner that exchanges heat between the refrigerant and the outside air, and a four-way valve for switching between cooling and heating operations, all arranged in the refrigerant circulation path. During cooling operation, by switching the four-way valve, the refrigerant is passed through the compressor, the outside air side heat exchanger, the expansion valve, and the heat transfer medium side heat exchanger in that order. This causes the heat transfer medium side heat exchanger to function as an evaporator, thereby cooling the heat transfer medium supplied from the circulation supply path 3. During heating operation, by switching the four-way valve, the refrigerant is passed through the compressor, the heat transfer medium side heat exchanger, the expansion valve, and the outside air side heat exchanger in that order. This causes the heat transfer medium side heat exchanger to function as a condenser, and the heat transfer medium supplied from the circulation supply line 3 is heated in the heat transfer medium side heat exchanger. In an air-cooled electric heat pump