Chillers, free cooling, heat pumps. 2 circuits up to 3 compressors per unit.
The press f. Parameter can also be used on units with as few as 2 compressors. The transducer will shut off one compressor. Wait 5 minutes (time out). Then the GR3 will turn the compressor back on. If the AP (HP) problem has been resolved the GR3 will allow the NRL to run. The NRL will shut down permanently if the allowable three (3) pre-alarm intervention number has been exceeded. If not the GR3 will allow the NRL to start up and run.