# US 2024/0200840 A1 · Heat source unit and refrigerant handling method

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 2024/0200840 A1
- Document ID: US20240200840A1
- Status: Published application
- Kind: A1
- Application number: 18/595,867
- Filed: 2024-03-05
- Published: 2024-06-20
- Earliest claimed: 2021-09-30
- Assignees: Daikin Industries, Ltd.
- Applicants: Daikin Industries, Ltd.
- Inventors: Shinsuke IKAWA; Katsunori MURATA
- Web page: https://patentgrep.com/patent/US20240200840A1

## CPC

- F25B 45/00: Arrangements for charging or discharging refrigerant
- F25B 13/00: Compression machines, plants or systems, with reversible cycle (defrosting cycles F25B47/02)
- F25B 41/20: Disposition of valves, e.g. of on-off valves or flow control valves (expansion valves F25B41/31)
- F25B 41/24: Arrangement of shut-off valves for disconnecting a part of the refrigerant cycle, e.g. an outdoor part
- F25B 49/005: {of safety devices (F25B49/02 and F25B49/04 take precedence)}
- F25B 49/02: for compression type machines, plants or systems
- F25B 2345/002: Collecting refrigerant from a cycle
- F25B 2345/003: Control issues for charging or collecting refrigerant to or from a cycle
- F25B 2345/006: characterised by charging or discharging valves
- F25B 2600/2519: On-off valves
- F25B: REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS

## Abstract

A first shut-off valve (46) and a second shut-off valve (47) are closed when power supply to a heat source unit (20) is stopped. At least one of the first shut-off valve (46) or the second shut-off valve (47) which corresponds to a stop valve (41, 42) having a first service port (44) is closer to a heat source heat exchanger (22) than the stop valve (41, 42) having the first service port (44) is.

## Claims

### Claim 1

A heat source unit connected to a utilization unit including a utilization heat exchanger, the heat source unit performing a refrigeration cycle using a refrigerant that circulates, the heat source unit comprising:
a compressor;
a heat source heat exchanger;
a gas line having one end joined to a gas end of the heat source heat exchanger;
a liquid line having one end joined to a liquid end of the heat source heat exchanger;
a first stop valve and a first shut-off valve which are connected to a portion of the gas line near another end of the gas line; and
a second stop valve and a second shut-off valve which are connected to a portion of the liquid line near another end of the liquid line, wherein
the first shut-off valve and the second shut-off valve are closed when power supply to the heat source unit is stopped,
at least one of the first stop valve or the second stop valve has a first service port, and
at least one of the first shut-off valve or the second shut-off valve which corresponds to the at least one of the stop valves having the first service port is closer to the heat source heat exchanger than the at least one of the stop valves having the first service port is.

### Claim 2 (depends on 1)

The heat source unit of claim 1, wherein
the first stop valve has the first service port, and
the first shut-off valve is closer to the heat source heat exchanger than the first stop valve is.

### Claim 3 (depends on 2)

The heat source unit of claim 2, wherein
the second shut-off valve is closer to the heat source heat exchanger than the second stop valve is.

### Claim 4 (depends on 1)

The heat source unit of claim 1 further comprising:
a third stop valve having a second service port, wherein
the third stop valve is closer to the heat source heat exchanger than the first shut-off valve of the gas line and the second shut-off valve of the liquid line are.

### Claim 5 (depends on 4)

The heat source unit of claim 4, wherein
the third stop valve is connected to the liquid line.

### Claim 6 (depends on 4)

The heat source unit of claim 4, wherein
an opening area of the second service port is greater than an opening area of the first service port.

### Claim 7 (depends on 1)

The heat source unit of claim 1, wherein
the refrigerant is a flammable refrigerant.

### Claim 8

A refrigerant handling method for handling a refrigerant with which a refrigerant circuit of a refrigeration apparatus is filled, the refrigeration apparatus including a utilization unit and a heat source unit, the refrigerant handling method comprising:
a first step of shutting off the refrigerant circuit between the utilization unit and the heat source unit on a site where the refrigeration apparatus is installed;
a second step of, after an end of the first step, sucking the refrigerant on a utilization unit side on the site where the refrigeration apparatus is installed; and
a third step of, after an end of the second step, sucking the refrigerant in the heat source unit through a facility that recovers the refrigerant.

### Claim 9 (depends on 8)

The method of claim 8 further comprising:
a fourth step of performing a pump-down operation to move the refrigerant on the utilization unit side to the heat source unit, wherein
the first step is performed after an end of the fourth step.

### Claim 10 (depends on 8)

The method of claim 8, wherein
the heat source unit includes:
a compressor;
a heat source heat exchanger;
a gas line having one end joined to a gas end of the heat source heat exchanger;
a liquid line having one end joined to a liquid end of the heat source heat exchanger;
a first stop valve and a first shut-off valve which are connected to a portion of the gas line near another end of the gas line; and
a second stop valve and a second shut-off valve which are connected to a portion of the liquid line near another end of the liquid line, wherein
the first shut-off valve and the second shut-off valve are closed when power supply to the heat source unit is stopped,
at least one of the first stop valve or the second stop valve has a first service port,
at least one of the first shut-off valve or the second shut-off valve which corresponds to the at least one of the stop valves having the first service port is closer to the heat source heat exchanger than the at least one of the stop valves having the first service port is, and
the first step includes:
a fifth step of closing the first shut-off valve and the second shut-off valve; and
a sixth step of closing the first stop valve and the second stop valve.

### Claim 11 (depends on 2)

The heat source unit of claim 2 further comprising:
a third stop valve having a second service port, wherein
the third stop valve is closer to the heat source heat exchanger than the first shut-off valve of the gas line and the second shut-off valve of the liquid line are.

### Claim 12 (depends on 3)

The heat source unit of claim 3 further comprising:
a third stop valve having a second service port, wherein
the third stop valve is closer to the heat source heat exchanger than the first shut-off valve of the gas line and the second shut-off valve of the liquid line are.

### Claim 13 (depends on 5)

The heat source unit of claim 5, wherein
an opening area of the second service port is greater than an opening area of the first service port.

### Claim 14 (depends on 2)

The heat source unit of claim 2, wherein
the refrigerant is a flammable refrigerant.

### Claim 15 (depends on 3)

The heat source unit of claim 3, wherein
the refrigerant is a flammable refrigerant.

### Claim 16 (depends on 4)

The heat source unit of claim 4, wherein
the refrigerant is a flammable refrigerant.

### Claim 17 (depends on 5)

The heat source unit of claim 5, wherein
the refrigerant is a flammable refrigerant.

### Claim 18 (depends on 6)

The heat source unit of claim 6, wherein
the refrigerant is a flammable refrigerant.

### Claim 19 (depends on 9)

The method of claim 9, wherein
the heat source unit includes:
a compressor;
a heat source heat exchanger;
a gas line having one end joined to a gas end of the heat source heat exchanger;
a liquid line having one end joined to a liquid end of the heat source heat exchanger;
a first stop valve and a first shut-off valve which are connected to a portion of the gas line near another end of the gas line; and
a second stop valve and a second shut-off valve which are connected to a portion of the liquid line near another end of the liquid line, wherein
the first shut-off valve and the second shut-off valve are closed when power supply to the heat source unit is stopped,
at least one of the first stop valve or the second stop valve has a first service port,
at least one of the first shut-off valve or the second shut-off valve which corresponds to the at least one of the stop valves having the first service port is closer to the heat source heat exchanger than the at least one of the stop valves having the first service port is, and
the first step includes:
a fifth step of closing the first shut-off valve and the second shut-off valve; and
a sixth step of closing the first stop valve and the second stop valve.

### Claim 20 (depends on 11)

The heat source unit of claim 11, wherein
the third stop valve is connected to the liquid line.