Dehumidification control strategy
A vehicle thermal system includes a thermal loop with a compressor, condenser, vapor injector, internal heat exchanger, chiller, and bypass valve, and a controller for operation during dehumidification. The controller opens an injector valve to inject vapor into the compressor and opens the bypass valve to reduce flow through the internal heat exchanger under a first condition.
1 . A vehicle thermal system comprising: a thermal loop including a compressor, condenser, vapor injector, internal heat exchanger, chiller, and bypass valve; and a controller programmed to, in response to a dehumidify request resulting in a dehumidification operation and in response to a first parameter value being less than a second parameter value, open an injector valve of the vapor injector such that the vapor injector injects vapor into the compressor, and open the bypass valve such that fluid-flow through the internal heat exchanger decreases.
2 . The vehicle thermal system of claim 1 , wherein the controller is further programmed to open the bypass valve such that refrigerant flows through the bypass valve instead of the internal heat exchanger before entering the compressor.
3 . The vehicle thermal system of claim 1 , wherein the internal heat exchanger and bypass valve are fluidly in parallel.
4 . The vehicle thermal system of claim 1 , wherein the controller is further programmed to, during the dehumidification operation, close the injector valve to control the vapor injected into the compressor.
5 . The vehicle thermal system of claim 1 , wherein the controller is further programmed to, during the dehumidification operation, close the injector valve to reduce the vapor injected into the compressor and close the bypass valve to increase flow through the internal heat exchanger before entering the compressor.
6 . The vehicle thermal system of claim 1 , wherein the controller is further programmed to, during the dehumidification operation while the bypass valve is open and an injector valve of the vapor injector is closed, open the injector valve such that the vapor injector injects vapor into the compressor and the bypass valve remains open.
7 . The vehicle thermal system of claim 1 , wherein the controller is further programmed to, during the dehumidification operation while the bypass valve is open and an injector valve of the vapor injector is closed, close the bypass valve such that flow through the internal heat exchanger increases and the injector valve remains closed.