Refrigerant Circuit Problems
System Condition 11
1. Low pressure gauge reading is too high.
2. High pressure gauge reading is too high.
Note: Ambient temperature is above 21°C (70°F).
3. The temperature of the air flow from the evaporator is warm.
Probable Cause
The condenser is not functioning properly.
Note: The system may have a normal or overcharge of refrigerant.
1. Check for a blockage in the flow of air through the condenser.
2. If a blockage is found in the condenser, remove all blockages and perform a performance check. The performance check will ensure proper system operation. Refer to "Performance Checks for the Air Conditioning System" section.
3. If the problem still exists, perform the following procedure. Check the system for an overcharge of refrigerant.
Note: Do not operate the engine.
* Recover the refrigerant. Refer to the Service Manual, SENR5664, "Refrigerant Recovery" section in Testing and Adjusting.
* Evacuate the system. Refer to the Service Manual, SENR5664, "Refrigerant System - Evacuate" section in Testing and Adjusting.
* Recharge the system with the correct amount of refrigerant. Measure the refrigerant by weight. Refer to the Service Manual, SENR5664, "Refrigerant System - Charge" section in Testing and Adjusting.
Note: With the ambient temperature above 21°C (70°F), the normal gauge reading for the low pressure side is 70 to 138 kPa (10 to 20 psi) while the normal gauge reading for the high pressure side is 820 to 1300 kPa (120 to 190 psi).
* In order to ensure the correct systems operation, perform a performance check. Refer to "Performance Checks for the Air Conditioning System" section.
4. If the low pressure gauge reading and the high pressure gauge readings are too high, perform the following procedure:
* Recover the refrigerant from the system. Refer to the Service Manual, SENR5664, "Refrigerant Recovery" section in Testing and Adjusting.
* Replace the receiver-dryer or replace the in-line dryer. Refer to the Service Manual, SENR5664, "Receiver-Dryer - Remove and Install" section in Disassembly and Assembly. For in-line dryers, refer to the Service Manual, SENR5664, "In-Line Refrigerant Dryer - Remove and Install" section in Disassembly and Assembly.
* If the receiver-dryer or the in-line dryer is not equipped with quick couplers, evacuate the system. Refer to the Service Manual, SENR5664, "Refrigerant System - Evacuate" section in Testing and Adjusting.
* Charge the system with the correct amount of refrigerant. Measure the refrigerant by weight. Refer to the Service Manual, SENR5664, "Refrigerant System - Charge" section in Testing and Adjusting.
* After the system is charged and operated for a minimum of ten minutes, perform a performance check. Refer to "Performance Checks for the Air Conditioning System" section.
