Indoor unit of air-conditioning apparatus having leaked refrigerant ventilation

Patent metadata

Field	Value
Publication number	US-10760839-B2
Application number	US-201515537013-A
Country	US
Kind code	B2
Filing date	Mar 26, 2015
Priority date	Mar 26, 2015
Publication date	Sep 1, 2020
Grant date	Sep 1, 2020

Abstract

In an indoor unit of an air-conditioning apparatus, an air inlet for room air is provided at a position lower than a height position of a drain pan. A partition plate is provided to partition a space below a height position of the drain pan in a housing. A pipe connecting portion connected to a refrigerant pipe of an outdoor unit is provided in one part of the partitioned space and a heat exchanger and a fan are placed in the other part of the partitioned space. At least one communicating path is formed in the partition plate to communicate the two parts of the partitioned space with each other. The indoor unit can include a controller for activating a fan when leakage of refrigerant is detected or for closing the communicating path when leakage of refrigerant is detected.

First claim

The invention claimed is:

1. An indoor unit of an air-conditioning apparatus, comprising:
a housing in which an air inlet and an air outlet for room air are provided;
a connection pipe provided with a pipe connecting portion connected to a refrigerant pipe of an outdoor unit through a relay pipe;
a heat exchanger configured to exchange heat between refrigerant flowing in from the outdoor unit through the connection pipe and air sucked into the housing;
a fan configured to suck air into the housing through the air inlet, and blow the air subjected to heat exchange by the heat exchanger out of the housing through the air outlet, to generate an air current;
a drain pan provided below the heat exchanger and configured to accumulate drain water caused by the heat exchange between the refrigerant and the air; and
a partition plate that is placed on a boundary between an airflow chamber and a pipe chamber, wherein
the air inlet, the heat exchanger, the fan, and the air outlet are located in the airflow chamber and are on a first side of the partition plate,
the pipe connecting portion is located in the pipe chamber and is on a second side of the partition plate, which is opposite to the first side of the partition plate,
the partition plate partitions a space below the height position of the drain pan in the housing,
the housing includes a panel, and the inlet is an opening formed in a lower part of the panel;
the air inlet is located below the drain pan,
a communicating path is formed in the partition plate to communicate the two parts of the partitioned space with each other, and
the refrigerant has a higher specific gravity than air, and the inlet is configured to serve as an outlet for refrigerant that leaks from the pipe connecting portion and passes through the partition plate via the communicating path when the fan is not operating.

2. The indoor unit of an air-conditioning apparatus of claim 1 , wherein the communicating path is placed at a position lower than the height position of the drain pan.

3. The indoor unit of an air-conditioning apparatus of claim 1 , wherein the communicating path is inclined toward the air outlet.

4. The indoor unit of an air-conditioning apparatus of claim 1 , wherein a total area of one side of an inlet-outlet of the communicating path is one half a total area of a corresponding side of the partition plate or smaller.

5. The indoor unit of an air-conditioning apparatus of claim 1 , wherein the communicating path comprises three or more communicating paths placed substantially at equal intervals.

6. The indoor unit of an air-conditioning apparatus of claim 1 , wherein the communicating path is placed at a position lower than a height position equivalent to one half a distance between a bottom face of the drain pan and a bottom face of the housing.

7. The indoor unit of an air-conditioning apparatus of claim 1 , further comprising:
a refrigerant detection sensor configured to detect leakage of the refrigerant; and
a controller configured to start the fan when refrigerant leakage is detected by the refrigerant detection sensor during standby for heating or cooling operation.

8. The indoor unit of an air-conditioning apparatus of claim 7 , wherein the refrigerant detection sensor is placed in the other part of the partitioned space in which the heat exchanger and the fan are placed, the refrigerant detection sensor is placed at a position lower than a height position of a bottom of the drain pan, and the refrigerant detection sensor is placed at a position lower than a height position of the communicating path.

9. The indoor unit of an air-conditioning apparatus of claim 1 , further comprising:
a refrigerant detection sensor configured to detect leakage of the refrigerant;
an opening and closing mechanism configured to open and close the communicating path; and
a controller configured to control the opening and closing mechanism to close the communicating path when no refrigerant leakage is detected by the refrigerant detection sensor and control the opening and closing mechanism to open the communicating path when refrigerant leakage is detected by the refrigerant detection sensor.

10. The indoor unit of an air-conditioning apparatus of claim 1 , further comprising:
an opening and closing mechanism configured to open and close the communicating path; and
a controller configured to control the opening and closing mechanism to periodically open and close the communicating path.

11. The indoor unit of an air-conditioning apparatus of claim 1 , further comprising:
a refrigerant detection sensor configured to detect leakage of the refrigerant;
a temperature detection sensor configured to obtain temperature in the housing; and
a controller configured to start the fan when refrigerant leakage is detected by the refrigerant detection sensor during standby for heating or cooling operation and the temperature obtained by the temperature detection sensor is lower than a preset temperature.

12. The indoor unit of an air-conditioning apparatus of claim 1 , further comprising:
a temperature detection sensor configured to obtain temperature in the housing; and
a controller configured to start the fan when the temperature obtained by the temperature detection sensor is lower than a preset temperature.

13. The indoor unit of an air-conditioning apparatus of claim 1 , wherein the refrigerant is a flammable refrigerant.

14. The indoor unit of an air-conditioning apparatus of claim 13 , wherein the flammable refrigerant is HFO-1234yf, HFO-1123, a mixture of HFO-1234yf or HFO-1123 and an HFC refrigerant, or a hydrocarbon-based refrigerant.

15. The indoor unit of an air-conditioning apparatus of claim 1 , wherein at least a part of the communicating path is located laterally of the inlet as viewed from a position facing the inlet.

Assignees

• Mitsubishi Electric Corp

Inventors

• Yamaguchi Kouji
• Makino Hiroaki
• Tazawa Tetsuya

Classifications

• F24F11/36

  to leakage of heat-exchange fluid · CPC title

• F24F1/0068 Primary

  characterised by the arrangement of refrigerant piping outside the heat exchanger within the unit casing · CPC title

• F24F13/222

  for evacuating condensate · CPC title

• F24F2110/00

  Control inputs relating to air properties · CPC title

• F25B49/02 Primary

  for compression type machines, plants or systems · CPC title