Hi i’m cezar
When i start the compressor, temperature increase low in unload mode, but when switch in load mode, temperature increase fast and if i am lucky not exceed 120 degrees C after which it drops to the working temperature ( now 87 degrees C). This compressor does not have thermostatic valve.
Thanks very much
Is you oil cooler clean? Is the cooling fan working? Can you check if the cooler feels hot, to make sure oil is actually flowing through it?
Is the oil filter clean and of the right type (usually, screw compressors have an oil-filter with built-in bypass valve, to make sure there’s oil flow even with a dirty filter).
If all this is ok, it could be the screw element. How many running hours does this machine have?