Patent ID: 9677788
Date: 2017-06-13
CPC Classifications: F25B

Claim:
1. A refrigerant system capable of operating at multiple capacity modes, the system comprising: an evaporator; a multi-stage compressor assembly having a first stage and a second stage; a first fluid flow path extending between the evaporator and the first stage; a second fluid flow path connected to the first fluid flow path and connected to the multi-stage compressor assembly between the first stage and the second stage; a first valve disposed along the first fluid flow path at or between the connection between the first fluid flow path and the second fluid flow path and the first stage, the first valve being arranged upstream from the multi-stage compressor assembly and responsive to control signals to selectively regulate flow of refrigerant to the first stage; and a second valve disposed along the second fluid flow path and responsive to control signals to selectively regulate flow of refrigerant along a bypass line; a heat exchanger, an economizer heat exchanger, and an expansion device; a main flow line extending from the multi-stage compressor assembly serially through the heat exchanger, economizer heat exchanger, and expansion device, and the evaporator; an economizer line connected to the main flow line and extending through the economizer heat exchanger to connect either directly to the bypass line or to the multi-stage compressor assembly between the first stage and the second stage; an economizer line valve disposed on the economizer line and movable between an open and closed position in response to control signals to selectively regulate flow of refrigerant along the economizer line; wherein the multiple capacity modes includes a first capacity mode and a second capacity mode, a capacity of the system in the first capacity mode being 150% the capacity of the system in the second capacity mode.