Refrigerant System Charge
Partial ChargeIf it was not necessary to completely empty the refrigerant system, a partial refrigerant charge can be added to the system.
CAUTION: Review all Safety Precautions and Warnings in the General Information before adding refrigerant to the system. Do not add refrigerant to a system that is known to have a leak.
NOTE: When connecting the service equipment coupling to the line fitting, verify that the valve of the coupling is fully closed. This will reduce the amount of effort required to make the connection. If connection is still difficult to make refer to TSB #24-02-93.
1. Attach manifold gauge set.
2. Set the air conditioning controls to A/C and Low blower speed.
3. Start the engine and allow it to warm up to normal running temperature.
4. If the air conditioning compressor does not engage, disconnect the Dual Pressure Cut Off switch.
Place a jumper wire across the terminals in the connector boot. If the compressor still does not engage, a problem exists in the compressor clutch feed circuit.
5. hold the engine speed at 1400 rpm.
6. While following the instructions provided with the charging equipment being used, charge through the suction side of the system. Add enough refrigerant to clear the sight glass in the filter drier.
7. At the point when the sight glass clears, note the weight of the refrigerant supply drum or the level in the charging cylinder. Add an additional 227 g (8 oz) of refrigerant to the system. Remove the jumper wire from the cut off switch connector and connect the cut off switch.
8. Test the overall performance of the air conditioner. Close all valves on the charging equipment and disconnect the hoses from the service ports. Install the service port caps.
Evacuation
Before adding refrigerant, all air must be evacuated from the system. Refer to Evacuating Refrigerant system.
Charging A/C System
The procedure below should be used to fill the refrigerant charge in the air conditioning system.
WARNING:
- REVIEW SAFETY PRECAUTIONS AND WARNINGS BEFORE CHARGING THE REFRIGERANT SYSTEM.
- AVOID BREATHING A/C REFRIGERANT AND LUBRICANT VAPOR OR MIST. EXPOSURE MAY IRRITATE EYES, NOISE AND THROAT. USE ONLY APPROVED SERVICE EQUIPMENT MEETING SAE REQUIREMENTS TO DISCHARGE R-134a SYSTEM. IF ACCIDENTAL SYSTEM DISCHARGE OCCURS, VENTILATE WORK AREA BEFORE RESUMING SERVICE.
- R-134a SERVICE EQUIPMENT OR VEHICLE A/C SYSTEM SHOULD NOT BE PRESSURE TESTED OR LEAK TESTED WITH COMPRESSED AIR. MIXTURE OF AIR and R-134a CAN BE COMBUSTIBLE AT ELEVATED PRESSURES. THESE MIXTURES ARE POTENTIALLY DANGEROUS AND MAY RESULT IN FIRE OR EXPLOSION CAUSING INJURY OR PROPERTY DAMAGE.
CAUTION: Do not overcharge refrigerant system, as excessive compressor head pressure can cause noise and system failure.
After the system has been tested for leaks and evacuated, a refrigerant (R-134a) charge can be injected into the system.
NOTE: When connecting the service equipment coupling to the line fitting, verify that the valve of the coupling is fully closed. This will reduce the amount of effort required to make the connection. If connection is still difficult to make refer to TSB #24- 02-93.
1. If using a separate vacuum pump close all valves before disconnecting pump. Connect manifold gauge set to the A/C service ports.
NOTE: The air conditioning system in this vehicle holds 850 grams (30 oz. or 1.88 lbs.) of R-134a refrigerant.
2. Measure refrigerant (refer to capacities) and heat to 52° C (125° F) with the charging station. Refer to the instructions provided with the equipment being used.
3. Verify engine is shut off. Open the suction and discharge valves. Open the charge valve to allow the heated refrigerant to flow into the system. When the transfer of refrigerant has stopped, close the suction and discharge valve.
4. If all of the charge did not transfer from the dispensing device, put vehicle controls into the following mode:
- Transmission in neutral
- Engine running at 1400 rpm
- A/C blower motor on Low speed
If the A/C compressor does not engage, test the compressor clutch control circuit and correct any failure.
5. Open the suction valve to allow the remaining refrigerant to transfer to the system.
WARNING: TAKE CARE NOT TO OPEN THE DISCHARGE (HIGH-PRESSURE) VALVE AT THIS TIME.
6. Close all valves and test the A/C system performance.
7. Disconnect the charging station or manifold gauge set. Install the service port caps.