A method for controlling the release of heat generated by a temperature control unit to an ambient environment outside an internal space, the temperature control unit configured to provide temperature control within the internal space, the method comprising: monitoring a heat release condition of the temperature control unit; determining, via a controller, whether to release the heat generated by the temperature control unit to an ambient environment outside of the internal space based on the heat release condition; operating a HVAC circuit of the temperature control unit in a heat release mode when the controller determines that the heat generated by the temperature control unit is to be released to the ambient environment outside the internal space; operating the HVAC circuit of the temperature control in a heat storage mode when the controller determines that the heat generated by the HVAC unit is not to be released to the ambient environment outside the internal space, characterized in that the heat release mode includes directing the refrigerant from a HVAC circuit compressor through a HVAC circuit condenser unit and preventing the refrigerant from passing through a phase change material reservoir; wherein the heat storage mode includes directing the refrigerant from a HVAC circuit compressor through the PCM reservoir and preventing the refrigerant from passing through the HVAC circuit condenser unit, wherein operating the temperature control unit in the heat release mode includes directing the refrigerant from the HVAC circuit condenser unit, through a HVAC circuit expansion device, through an evaporator unit and back to the HVAC circuit compressor; and wherein operating the temperature control unit in the heat release mode includes directing a second refrigerant through the HVAC circuit via a PCM heat release path that includes: directing the second refrigerant from an auxiliary compressor through an auxiliary condenser unit, through an auxiliary expansion device, through the PCM reservoir and back to the auxiliary compressor. monitoring a heat release condition of the temperature control unit; determining, via a controller, whether to release the heat generated by the temperature control unit to an ambient environment outside of the internal space based on the heat release condition; operating a HVAC circuit of the temperature control unit in a heat release mode when the controller determines that the heat generated by the temperature control unit is to be released to the ambient environment outside the internal space; operating the HVAC circuit of the temperature control in a heat storage mode when the controller determines that the heat generated by the HVAC unit is not to be released to the ambient environment outside the internal space, characterized in that the heat release mode includes directing the refrigerant from a HVAC circuit compressor through a HVAC circuit condenser unit and preventing the refrigerant from passing through a phase change material reservoir; wherein the heat storage mode includes directing the refrigerant from a HVAC circuit compressor through the PCM reservoir and preventing the refrigerant from passing through the HVAC circuit condenser unit, wherein operating the temperature control unit in the heat release mode includes directing the refrigerant from the HVAC circuit condenser unit, through a HVAC circuit expansion device, through an evaporator unit and back to the HVAC circuit compressor; and wherein operating the temperature control unit in the heat release mode includes directing a second refrigerant through the HVAC circuit via a PCM heat release path that includes: directing the second refrigerant from an auxiliary compressor through an auxiliary condenser unit, through an auxiliary expansion device, through the PCM reservoir and back to the auxiliary compressor.