Abstract: A method for controlling a vapour compression system (1) is disclosed. The vapour compression system (1) has an ambient temperature sensor (8) arranged to measure an ambient temperature. A time period during which the ambient temperature sensor (8) is unexposed to solar heating is selected. During the selected time period, measurements of the ambient temperature are obtained by means of the ambient temperature sensor (8), and measurements of at least one further parameter related to the vapour compression system (1) are obtained, while operating the vapour compression system (1). Model parameters for a model of at least a part of the vapour compression system (1) are derived, based on the obtained measurements, the model providing correlation between the ambient temperature and the at least one further parameter.

Abstract: A method for monitoring a refrigerant charge in a vapour compression system (1) is disclosed, the vapour compression system (1) including a compressor unit (2), a heat rejecting heat exchanger (3), a high pressure expansion device (4), a receiver (5), at least one expansion device (9, 10), and at least one evaporator (11, 12) arranged in a refrigerant path. A change in net mass flow into or out of the receiver (5) and/or a change in net enthalpy flow into or out of the receiver (5) is detected, and a pressure inside the receiver (5) is monitored as a function of time, following the detected change in net mass flow and/or in net enthalpy flow. A time constant being representative for dynamics of the receiver (5) is derived, based on the monitored pressure as a function of time, and information regarding a refrigerant charge in the vapour compression system (1) is derived, based on the derived time constant.

Abstract: A method for controlling a vapour compression system (1) is disclosed. The vapour compression system (1) has an ambient temperature sensor (8) arranged to measure an ambient temperature. A time period during which the ambient temperature sensor (8) is unexposed to solar heating is selected. During the selected time period, measurements of the ambient temperature are obtained by means of the ambient temperature sensor (8), and measurements of at least one further parameter related to the vapour compression system (1) are obtained, while operating the vapour compression system (1). Model parameters for a model of at least a part of the vapour compression system (1) are derived, based on the obtained measurements, the model providing correlation between the ambient temperature and the at least one further parameter.

Abstract: A method for monitoring a refrigerant charge in a vapour compression system (1) is disclosed, the vapour compression system (1) including a compressor unit (2), a heat rejecting heat exchanger (3), a high pressure expansion device (4), a receiver (5), at least one expansion device (9, 10), and at least one evaporator (11, 12) arranged in a refrigerant path. A change in net mass flow into or out of the receiver (5) and/or a change in net enthalpy flow into or out of the receiver (5) is detected, and a pressure inside the receiver (5) is monitored as a function of time, following the detected change in net mass flow and/or in net enthalpy flow. A time constant being representative for dynamics of the receiver (5) is derived, based on the monitored pressure as a function of time, and information regarding a refrigerant charge in the vapour compression system (1) is derived, based on the derived time constant.