I have an INGERSOLRAND Reciprocating compressor. I have the following problem: air is released from the saftyvalve on the inter cooler.
Assuming that the safetyvalve itself is fine (don't see too many problems with those), you probably have problems with your high-pressure cylinder.
Let me explain..
The intercooler sits between the low-pressure and high-pressure stage of the reciprocating (piston) compressor.
Stage (cylinder/piston) one compresses the air to the medium level. Because of the compression, the air becomes very hot. That's why the compressed air is cooled by the intercooler.
The cooled air is further compressed by the second stage to the desired end pressure.
The compressor is designed in such a way that there is a balance between the low-pressure and the high-pressure stage.
The air that is pumped out by the low-pressure stage is sucked in by the high-pressure stage (the same amount of air in liters/minute or cubic feet per second).
So, if the high-pressure stage isn't working properly, the low-pressure stage pumps in more air than is taken out by the high-pressure stage.
This way, the pressure in the intercooler will rise, until the safety valve blows.
My advice: look for problems with your high-pressure stage. Could be broken valves or something stuck there.
Hope this was of any help.. good luck!