ESIE12-06 Troubleshooting by Remote ControllerService Diagnosis 197Evaluation of Abnormal Low PressureAbnormally low pressure level is mostly caused by the evaporator side. The following contents are providedbased on field checking of service engineer. Further, the number is listed in the order of degree of influence.In Cooling OperationIn Heating OperationCHECK 3Check items (Possible causes) JudgementDoes the outdoor unit fan run normally? Visual inspectionIs the indoor unit filter clogged? Visual inspectionIs there clogging before or after the EV (capillary)? Check if there is a temperature difference before andafter EV (capillary).Check if the main valve unit of EV operates (by noise,vibration).Is the check valve clogged? Check if there is a temperature difference before andafter check valve. If YES, the check valve is caught.Is the indoor unit installed under such conditions thatshort circuit easily occurs? Visual inspectionIs the refrigerant gas short? Conduct refrigerant collection and vacuum drying, andthen add proper amount refrigerant.Check items (Possible causes) JudgementDoes the outdoor unit fan run normally? Visual inspectionIs the outdoor unit heat exchanger clogged? Visual inspectionIs the outdoor unit installed under such conditions thatshort circuit easily occurs? Visual inspectionIs there clogging before or after the EV (capillary)? Check if there is a temperature difference before andafter EV (capillary).Check if the main valve unit of EV operates (by noise,vibration).Is the check valve clogged? Check if there is a temperature difference before andafter check valve. If YES, the check valve is caught.Is the refrigerant gas short? Conduct refrigerant collection and vacuum drying, andthen add proper amount refrigerant.
