I have a Few questions before trying to answer.Does the pressure go up quickly to 200 psi and down to 120 psi or does the pressure build slowly to 200 psi and slowly down to 120 Psi. Does this unit have a dryer built in or in the system. Are the pressures set correctly on the intellisys. Does this unit have modulation. What mode of operation is unit in.
Pressure building up fast is an indication of an obstruction in the discharge line. It could be a valve positioned wrong or a dryer froze up. If the pressure builds slowly up and down it sounds like the intellisys settings are incorrect. If the unit has modulation and is operating in modulation it sounds like the cash regulator needs adjusting.