Carrier 30gx low oil level alarm

[abcxyz5]

Hi

i have carrier chiller 30gx and experiencing low oil level for circuit A but I couldn't see any leak.

The circuit has been in normal conditions for almost a year and half since compressor changed.

What might be the cause and suggested solution?

[seanf]

Might be that the circuit is low on refrigerant. Check how the circuit is performing, check the sight glass, leak check the refrigerant circuit.

Might be that circuit A has been running at low capacity for long periods. Run circuit A on a high heat load, so that it runs for a long period at full capacity. See if that returns the oil.

Might be the oil is getting trapped in the economizer heat exchanger. Run circuit A at full capacity so that the economizer is brought into use, and see how the economizer is performing.

Might be a problem with the oil seperator. Check the others suggestions first.