228 and 230 which may be optionally included separately or together as additional tests or as a substitution for the test performed at step 226 in step 228 a test is performed to see if the incoming line voltage is low a low line voltage condition would be indicative for example of a brownout condition if the line voltage is low control proceeds to step 232 where the alert flag is tested as described above step 230 tests to determine whether the compressor current is high if the current is high this can be indicative of a maximum load or brownout condition and control similarly proceeds to step 232 where the alert flag is tested it should be understood that the flowchart of fig3 b illustrates several redundant tests useful in determining when the maximum load condition exists in an actual commercial embodiment it may not be necessary to include all of these tests for example suitable results could be obtained using only tests 220 and 226 or tests 220 and 228 or tests 220 and 230 for example also while the use of an alert flag has been illustrated this is but one way of implementing the logic performed by the system of the invention other equivalent flowcharts can be constructed to accomplish the same results by increasing the refrigerant flow in response to sensing the existence of or onset of a.