US 12,595,942 B2 · Refrigerant circuit suction heat control

Abstract

A method is directed to controlling superheat in a refrigerant circuit containing working fluid. The method includes directing a suction stream of the working fluid from the evaporator through the suction heat exchanger and directing the working fluid compressed by the compressor to the suction heat exchanger. The method also includes controlling a flowrate of the compressed working fluid through the suction heat exchanger. The controlling includes modulating a working fluid control valve based on a determined target saturation temperature for the compressed working fluid. A refrigerant circuit includes a main flow path, a bypass flow path, a working fluid control valve, and a controller for the refrigerant circuit. The controller configured to determine a target saturation temperature for the working fluid flowing through the suction heat exchanger in the bypass flow path, and modulate the working fluid control valve based on the target saturation temperature.

Claims19

Dependent claims

A method of controlling superheat in a refrigerant circuit, the refrigerant circuit including a compressor, a condenser, an expander, an evaporator, a suction heat exchanger, the refrigerant circuit containing a working fluid, the method comprising:

directing a suction stream of the working fluid from the evaporator through the suction heat exchanger to the compressor;
directing a first portion of the working fluid compressed by the compressor from the compressor to the suction heat exchanger;
and
controlling, with a working fluid control valve, a flowrate of the first portion of the working fluid into the suction heat exchanger, which includes:
detecting properties of the working fluid,
determining a target saturation temperature for the first portion of the working fluid based on a suction superheat setpoint and the detected properties of the working fluid, and
modulating the working fluid control valve based on the determined target saturation temperature.

4 more elements

A refrigerant circuit for a heating, ventilation, air conditioning, and refrigeration (HVACR) system, comprising:

a compressor, a condenser, an expander, an evaporator, and a suction heat exchanger being fluidly connected,
a main flow path extending from the compressor through the condenser, the expander, the evaporator, and the suction heat exchanger, and back to the compressor;
a bypass flow path extending through the suction heat exchanger, the bypass flow path extending from the main flow path downstream of the compressor and upstream of the condenser in the main flow path, the bypass flow path extending to the main flow path downstream of the expander and upstream of the suction heat exchanger;
a working fluid control valve for controlling flow of working fluid through the bypass flow path;
one or more sensors;
a controller for the refrigerant circuit, the controller configured to:
detect, using the one or more sensors, properties of the working fluid,
determining a target saturation temperature for the working fluid in the bypass flow path flowing through the suction heat exchanger based on a predetermined suction superheat setpoint and the detected properties of the working fluid, and
modulate the working fluid control valve based on the determined target saturation temperature.

6 more elements

Dependencies are inferred from the claim text.

Refrigerant circuit suction heat control

Life of this patent

Refrigerant circuit suction heat control

Life of this patent

Abstract

Claims19