corudstr
10-06-2016, 09:13 AM
I have a Carrier 5H60 using R507 to operate a Northstar ice maker. I have a problem with low oil pressure. I suspect there is some kind of problem with the hydraulic unloader system.
Compressor had a leaky shaft seal, while replacing the shaft seal some metallic debris was noticed behind the seal. Inspected inside of compressor and found wore out connecting rod bearings. I do not have any records of its operating condition before this. Replaced crank, rods, bearings, oil pump.
Upon start up there is no apparent oil pressure, after the compressor runs for a few maybe 10 seconds you can here a sudden clatter that I believe is one or more of the cylinders loading up, immediately after the cylinders load the oil pressure rises. The pressure comes up to about 20 to 25 psi, the book says it should be 45 to 50. While testing the machine it has been started and run numerous times, occasionally I have seen 50 psi, but only intermittently.
If the compressor is running and you close the liquid line solenoid the system will continue to run for a minute or two, about the time that you would expect all of the liquid to be boiled out of the ice maker drum when you would normally see the suction pressure drop instead the oil pressure drops to 0. I think the suction pressure may drop a little bit and the compressor unloads and then loses oil pressure.
Why does the oil pressure only seem to come up when the compressor loads?
Why is the oil pressure so low?
Thank you for any help you may provide.
C.O.
Compressor had a leaky shaft seal, while replacing the shaft seal some metallic debris was noticed behind the seal. Inspected inside of compressor and found wore out connecting rod bearings. I do not have any records of its operating condition before this. Replaced crank, rods, bearings, oil pump.
Upon start up there is no apparent oil pressure, after the compressor runs for a few maybe 10 seconds you can here a sudden clatter that I believe is one or more of the cylinders loading up, immediately after the cylinders load the oil pressure rises. The pressure comes up to about 20 to 25 psi, the book says it should be 45 to 50. While testing the machine it has been started and run numerous times, occasionally I have seen 50 psi, but only intermittently.
If the compressor is running and you close the liquid line solenoid the system will continue to run for a minute or two, about the time that you would expect all of the liquid to be boiled out of the ice maker drum when you would normally see the suction pressure drop instead the oil pressure drops to 0. I think the suction pressure may drop a little bit and the compressor unloads and then loses oil pressure.
Why does the oil pressure only seem to come up when the compressor loads?
Why is the oil pressure so low?
Thank you for any help you may provide.
C.O.