Systems and methods for detecting and responding to refrigerant leaks in heating, ventilating, and air conditioning systems

Patent metadata

Field	Value
Publication number	US-11060746-B2
Application number	US-201815874630-A
Country	US
Kind code	B2
Filing date	Jan 18, 2018
Priority date	Dec 1, 2017
Publication date	Jul 13, 2021
Grant date	Jul 13, 2021

Abstract

The present disclosure relates to a heating, ventilating, and air conditioning (HVAC) system that includes a refrigerant circuit and a sensor configured to measure a refrigerant concentration external to the refrigeration circuit. The HVAC system also includes a controller that is communicatively coupled to the sensor and to an economizer. The controller is configured to control a flow of environmental air into the HVAC system. The controller is further configured to increase a ratio of the flow of environmental air relative to a flow of return air from a conditioned interior space of a building when the sensor measures the refrigerant concentration above a predetermined threshold concentration.

First claim

The invention claimed is:

1. A heating, ventilating, and air conditioning (HVAC) system comprising:
a first HVAC unit having a first economizer comprising a damper having at least one baffle, wherein the first economizer is configured to control a first flow of environmental air into the HVAC system;
a first sensor configured to measure a first leaked refrigerant concentration within the HVAC system;
a first controller communicatively coupled to the first sensor and the first economizer, wherein the first controller is configured to adjust the at least one baffle of the first economizer to increase a first ratio of the first flow of environmental air relative to a first flow of return air from a conditioned interior space of a building when the first sensor measures the first leaked refrigerant concentration above a predetermined threshold concentration;
a second HVAC unit, wherein the second HVAC unit comprises a second economizer configured to control a second flow of environmental air into the HVAC system;
a second sensor configured to measure a second leaked refrigerant concentration near the second HVAC unit; and
a second controller communicatively coupled to the second sensor and the second economizer, wherein the second controller is configured to increase a second ratio of the second flow of environmental air relative to a second flow of return air from the conditioned interior space of the building when the second sensor measures the second leaked refrigerant concentration above the predetermined threshold concentration.

2. The HVAC system of claim 1 , wherein the first controller of the first HVAC unit and the second controller of the second HVAC unit are communicatively coupled, wherein the first controller is configured to increase the second ratio of the second flow of environmental air relative to the second flow of return air when the first sensor measures the first leaked refrigerant concentration above the predetermined threshold concentration.

3. The HVAC system of claim 1 , wherein the first sensor is disposed upstream of supply ductwork of the HVAC system and is configured to measure the first leaked refrigerant concentration in conditioned air before the conditioned air enters the supply ductwork of the HVAC system.

4. The HVAC system of claim 1 , wherein the HVAC system comprises an alarm and the first controller is configured to activate the alarm when the first sensor measures the first leaked refrigerant concentration above the predetermined threshold concentration.

5. The HVAC system of claim 1 , wherein the first controller is configured to send a notification to an electronic device when the first sensor measures the first leaked refrigerant concentration above the predetermined threshold concentration.

6. A heating, ventilating, and air conditioning (HVAC) system comprising:
a first HVAC unit, wherein the first HVAC unit comprises:
an economizer comprising a damper having at least one baffle, wherein the economizer is configured to control a flow of environmental air into the HVAC system;
a first sensor configured to measure a first leaked refrigerant concentration within the HVAC system;
a first controller communicatively coupled to the first sensor and the economizer, wherein the first controller is configured to adjust the at least one baffle of the economizer to increase a ratio of the flow of environmental air relative to a flow of return air from a conditioned interior space of a building when the first sensor measures the first leaked refrigerant concentration above a predetermined threshold concentration; and

a second HVAC unit, wherein the second HVAC unit comprises:
a second sensor configured to measure a second leaked refrigerant concentration near the second HVAC unit;
a second controller communicatively coupled to the second sensor and the first controller, wherein the first controller is configured to increase the ratio of the flow of environmental air relative to the flow of return air when the second sensor measures the second leaked refrigerant concentration above the predetermined threshold concentration.

7. The HVAC system of claim 6 , wherein the second HVAC unit does not include a respective economizer.

8. The HVAC system of claim 6 , wherein the second sensor is disposed within ductwork of the conditioned interior space.

Assignees

• Johnson Controls Tech Co

Inventors

• Maddox Steven M
• Mcquade William F

Classifications

• F24F1/0041

  characterised by exhaustion of inside air from the room (in combination with simultaneous introduction of outside air F24F1/0038) · CPC title

• F24F2110/65

  Concentration of specific substances or contaminants · CPC title

• F24F11/36 Primary

  to leakage of heat-exchange fluid · CPC title

• F24F7/007

  with forced flow (using ducting systems F24F7/06) · CPC title

• F24F11/70

  Control systems characterised by their outputs; Constructional details thereof · CPC title