A method for modular refrigeration unit (MRU) health monitoring includes receiving log data on a log data input from the MRU by a MRU health monitor, the log data comprising a plurality of datapoints, each of the plurality of datapoints comprising a position of a control valve of the MRU and a corresponding time; determining by the MRU health monitor a plurality of MRU parameters from the log data; determining a plurality of MRU health flags based on the MRU parameters; adding the plurality of MRU health flags to determine an MRU health score; determining whether the MRU health score is higher than a replacement threshold; and indicating replacement of the MRU in the event the MRU health score is higher than the replacement threshold.