A/C PERFORMANCE TEST — Performance Test Diagnoses (Cont'd, page 2)
HA-36spec tablePerformance Test Diagnoses (Cont'd)
Performance test diagnoses (page 2 of N) — expansion valve overflow / air in system / moisture in system
EXPANSION VALVE OVERFLOW (AC355A)
SymptomInsufficient cooling. Sweat on suction line.
Probable causeExpansion valve allows too much refrigerant through evaporator.
Corrective actionCheck valve for operation. If suction side does not show a pressure decrease, replace valve.
MALFUNCTIONING EXPANSION VALVE (AC356A)
SymptomNo cooling. Sweat or frosting on suction line.
Probable causeMalfunctioning expansion valve.
Corrective action1. Discharge system. 2. Replace valve. 3. Evacuate and charge system.
AIR IN SYSTEM (AC359A)
SymptomInsufficient cooling. Sight glass shows occasional bubbles.
Probable causeAir mixed with refrigerant in system.
Corrective action1. Discharge system. 2. Replace receiver drier. 3. Evacuate and charge system.
MOISTURE IN SYSTEM (AC360A)
SymptomAfter short operation, suction side may show vacuum pressure reading. During this condition, discharge air will be warm. As a warning of this, reading vibrates around 39 kPa (0.39 bar, 0.4 kg/cm², 6 psi).
Probable causeDrier is saturated with moisture. Moisture has frozen in expansion valve. Refrigerant flow is restricted.
Corrective action1. Discharge system. 2. Replace receiver drier (twice if necessary). 3. Evacuate system completely. (Repeat 30 minutes evacuating three times.) 4. Recharge system.
| Specification | Value |
|---|---|
| MOISTURE IN SYSTEM warning low-side readingReading vibrates around this value. | ≈ 39kPa (0.39 bar, 0.4 kg/cm², 6 psi) |
MOISTURE IN SYSTEM warning low-side readingReading vibrates around this value.
≈ 39kPa (0.39 bar, 0.4 kg/cm², 6 psi)