Commercial Air Conditioner Model: AP*****EAA AU*****EAA239. Refrigerant circuitAU182AEEAAAU242AGEAA, AU48NAIEAA, AU60NAIEAA1. high pressure switch 2. low pressure switchcoolingheatingevaporatorindoor coil temp. sensor3-way stopvalvesuction temp. sensordischarging temp.sensormaintenancevalve4-way valvesingle checkvalvemaincapillarysub-capillarycompressorstop valvecondenserdefrost temp. sensormufflecompressor air-liquidsegregatorcheck valvecheckvalve4-way valve3-way stopvalve (air side)coiltemp.sensorevaporator21capillary3-way stopvalve (liquidside)cooling heatingdefrosttemp.sensorcondenserdischarging temp. sensorheater