Diagnostics for variable-capacity compressor control systems and methods

A method comprising:

• receiving, with a control module, a demand signal from a thermostat;
• determining, with the control module, that at least one of communication with an outdoor-air-temperature sensor that generates outdoor-air-temperature data corresponding to an outdoor-air temperature has been interrupted and the outdoor-air-temperature indicated by the outdoor-air-temperature data is outside of a predetermined temperature range;
• operating, with the control module, a variable-capacity compressor operable at a first capacity and at a second capacity that is higher than the first capacity, the control module operating the variable-capacity compressor in a first mode in response to determining that there is communication with the outdoor-air-temperature sensor and the control module and that the outdoor-air-temperature indicated by the outdoor-air-temperature data is within the predetermined range, the control module operating the variable-capacity compressor in a fault mode in response to determining that at least one of communication with the outdoor-air-temperature sensor has been interrupted and that the outdoor-air-temperature indicated by the outdoor-air-temperature data is outside of the predetermined temperature range;
• wherein the control module operates the variable-capacity compressor in the first mode by switching the variable-capacity compressor between the first capacity and the second capacity based on the demand signal and the outdoor-air-temperature data and operates the variable-capacity compressor in the fault mode by operating the variable-capacity compressor at one of the first capacity and the second capacity based on the demand signal.

A system comprising:

• a variable-capacity compressor operable at a first capacity and at a second capacity that is higher than the first capacity;
• an outdoor-air-temperature sensor that generates outdoor-air-temperature data corresponding to an outdoor-air temperature;
• a current sensor that generates electrical current data corresponding to electrical current delivered to the compressor;
• a control module that receives a demand signal from a thermostat, the outdoor-air-temperature data, and the electrical current data, that switches the variable-capacity compressor between the first capacity and the second capacity based on the outdoor-air-temperature data and the demand signal, and that determines whether the electrical current data indicates an expected change in the electrical current being delivered to the compressor when the variable-capacity compressor is switched between the first capacity and the second capacity;
• wherein, in response to determining that the electrical current data does not indicate the expected change in the electrical current being delivered to the compressor when the variable-capacity compressor is switched between the first capacity and the second capacity, the control module performs at least one of operating the variable-capacity compressor in a fault mode, generating an alert indicating that the variable-capacity compressor is operating in the fault mode, and mitigating actions.

A method comprising:

• generating, with an outdoor-air-temperature sensor, outdoor-air-temperature data corresponding to an outdoor-air temperature;
• generating, with a current sensor, electrical current data corresponding to electrical current delivered to the compressor;
• receiving, with a control module, the outdoor-air-temperature data, the electrical current data, and a demand signal from a thermostat;
• switching, with the control module, a variable-capacity compressor between operation in a first capacity and a second capacity that is higher than the first capacity based on the outdoor-air-temperature data and the demand signal;
• determining, with the control module, whether the electrical current data indicates an expected change in the electrical current being delivered to the compressor when the variable-capacity compressor is switched between the first capacity mode and the second capacity mode;
• performing, with the control module, at least one of operating the variable-capacity compressor in a fault mode, generating an alert indicating that the variable-capacity compressor is operating in the fault mode, and mitigating actions in response to determining that the electrical current data does not indicate the expected change in the electrical current being delivered to the compressor when the variable-capacity compressor is switched between the first capacity and the second capacity.

A method comprising:

• generating, with an outdoor-air-temperature sensor, outdoor-air-temperature data corresponding to an outdoor-air temperature;
• receiving, with a control module, a demand signal from a thermostat;
• determining, with the control module, whether a variable-capacity compressor, that is operable at a first capacity and at a second capacity that is higher than the first capacity, has been activated since a most recent power cycling of the variable-capacity compressor in response to receiving the demand signal;
• operating, with the control module, the variable-capacity compressor at the second capacity for at least a predetermined time period in response to determining that the variable-capacity compressor has not been activated since the most recent power cycling of the variable-capacity compressor;
• switching, with the control module, the variable-capacity compressor between the first capacity and the second capacity based on the demand signal and the current outdoor air temperature in response to determining that the variable-capacity compressor has been activated since the most recent power cycling of the variable-capacity compressor.