Cooling output too low (possible compressor cycling)

Thermostatic expansion valve fault (e.g. superheat too high, orifice too small, lost charge, partial blockage).

Set thermostatic expansion valve to a lower superheat setting or check if a bigger orifice will bring the superheat down. When changing / removing the orifice, check if dirt etc. blocks the valve (clean it). If the sensor bulb charge is lost, warming up the bulb with your hand will not open the valve. If the charge is still there it will open.