Testing the Refrigerant System
If you suspect a problem in the refrigerant system, check for the following conditions:
- Check the outer surfaces of the radiator and the condenser cores to be sure that the airflow is not blocked by dirt, leaves, or other foreign material. Check between the condenser and the radiator, as well as all outer surfaces.
- Check for restrictions or kinks in the condenser core, the hoses, and the tubes.
- Check the operation of the blower fan.
- Check all the air ducts for leaks or restrictions. Low airflow rate may indicate a restricted evaporator core.
- Check for slippage of the compressor clutch.
- Check the drive belt tension.
Insufficient Cooling "Quick Check" Procedure
Perform the following "hand-feel" procedure to get a quick idea of whether the A/C system has the proper charge of Refrigerant-134a. The air temperature must be above 21°C (70°F) for most models.
- Warm up the engine. Run the engine at idle.
- Open the hood and all the doors.
- Turn the A/C switch ON.
- Set the temperature control to the full cold position.
- Set the blower speed switch on the maximum speed setting.
- "Hand-feel" the temperature of the evaporator outlet pipe. The pipe should be cold.
- Check for other problems. Refer to "Testing the Refrigerant System" .
- Leak check the system. Refer to "Leak Testing the Refrigerant System" in this section. If you find a leak, discharge the system and repair the leak as required. After completing the repair, evacuate the system and charge it.
- If there is no leak, refer to Too Hot in Vehicle .
Temperature °C (°F)* | Pressure kPa (psig)* | Temperature °C (°F)* | Pressure kPa (psig)* |
|---|---|---|---|
-8 (17.6) | 113.1 (16.4) | 9 (48.2) | 296.2 (43.0) |
-7 (19.4) | 121.5 (17.6) | 10 (50.0) | 309.6 (44.9) |
-6 (21.2) | 130.2 (18.9) | 15 (59.0) | 383.7 (55.7) |
-5 (23.0) | 139.1 (20.2) | 20 (68.0) | 467.7 (67.8) |
-4 (24.8) | 148.4 (21.5) | 25 (77.0) | 567.5 (82.3) |
-3 (26.6) | 157.9 (22.9) | 30 (86.0) | 667.8 (96.9) |
-2 (28.4) | 167.6 (24.3) | 35 (95.0) | 785.6 (113.9) |
-1 (30.2) | 177.8 (25.8) | 40 (104.0) | 916.4 (133.0) |
0 | 188.2 (27.3) | 45 (113.0) | 1 062.2 (154.0) |
1 (33.8) | 198.8 (28.8) | 50 (122.0) | 1 222.1 (177.2) |
2 (35.6) | 209.9 (30.4) | 55 (131.0) | 1 398.2 (202.8) |
3 (37.4) | 221.2 (32.1) | 60 (140.0) | 1 589.6 (230.5) |
4 (39.2) | 232.9 (33.8) | 65 (149.0) | 1 799.0 (260.9) |
5 (41.0) | 245.0 (35.5) | 70 (158.0) | 2 026.6 (293.9) |
6 (42.8) | 257.4 (37.3) | 75 (167.0) | 2 272.2 (329.5) |
7 (44.6) | 269.8 (39.1) | 80 (176.0) | 2 544.0 (369.0) |
8 (46.4) | 282.9 (41.0) | -- | -- |
* All calculated values are rounded to one decimal place. Evaporator Range: From -7 to +7°C (+19.4 to +44.6°F), the temperatures represent the gas temperatures inside the coil and not on the coil surfaces. Add 2 to 6°C (4 to 11°F) to the coil and air-off temperatures. Condenser Range: From 45-70°C (113-158°F), the temperatures are not ambient. Add 19-22°C (34-40°C) to the ambient temperatures for proper heat transfer. Then refer to the pressure chart. Example: 32°C (90°F) Ambient temperature + 22°C (40°F) = 54°C (130°F) Condenser temperature, which yields 1 379 kPa (200 psig), based on 50 km/h (31 mph) airflow. | |||
