Mhobson
16-04-2012, 06:37 PM
I'm new to this forum. We build ice vending machines and control the condensing unit with our own controls.
Here is our issue/concern. We are using R-404 with Polyolester oil. our condensing unit has 2 fans that are controlled to operate at 2 pressures. One at 210psi and the other kicks on at 250psi. Our high pressure cut out is 350 psi. We have more than 100 units out running this way without issues.
One of the fans failed and the unit ran for an unknown perion of time without reaching 350 and faulting at the 350psi cut out. We believe that the unit ran at a much higher than normal pressure for a long period of time. Could running at, say 310psi for days, cause a problem with the oil or something else? The sight glass on the compressor is brownish/grey when normally it is a clear oil. We are not experts in refrigeration but are fairly good with controls. If we need to have a secondary or another safeguard we can monitor the high pressure and if over a certain number, 300, and it is there for a certain length of time then we can issue a fault then.
Thanks in advance for any help!
Here is our issue/concern. We are using R-404 with Polyolester oil. our condensing unit has 2 fans that are controlled to operate at 2 pressures. One at 210psi and the other kicks on at 250psi. Our high pressure cut out is 350 psi. We have more than 100 units out running this way without issues.
One of the fans failed and the unit ran for an unknown perion of time without reaching 350 and faulting at the 350psi cut out. We believe that the unit ran at a much higher than normal pressure for a long period of time. Could running at, say 310psi for days, cause a problem with the oil or something else? The sight glass on the compressor is brownish/grey when normally it is a clear oil. We are not experts in refrigeration but are fairly good with controls. If we need to have a secondary or another safeguard we can monitor the high pressure and if over a certain number, 300, and it is there for a certain length of time then we can issue a fault then.
Thanks in advance for any help!