I have a condenser with 5 fans and a controller with 4 stages, the last 2 fans come on at the same time. The system is a freezer running on r404a and there is a few issues we are having . My boss is telling me to set the first fan to come on at 250 psi or about 40 degrees , the other fans are set to come on at 15 psi intervals after that, he seems to think that it might be over condensing with the cooler nights ,( its getting down to 0c), if it is running at around 220-230psi . i thought that if the pressures were 12 to 20 psi above ambient then we are in the right zone. Is there any point of having a high set point ?? dont we lose efficency with the compression ratio being higher?
Also when the second fan cuts in and the pressure drops the liquid in the sight glass disappears until fan has cycled off and pressure raises again . Is the differential between fans to high?
thank you for any answers or advice you may have