This procedure covers evacuating, vacuum testing, and recharging the R-134a refrigerant in the AC system of a 2015 Kia Forte with 1.8L engine to restore proper cooling performance.

Warnings

Tools required

Parts

• R-134a refrigerant × 1 — Use OEM specification
• PAG oil (if needed) × 1 — Use OEM PAG 46 or equivalent
• AC system UV dye (optional) × 1 — Use OEM specification

Preparation

1. Park vehicle on level surface and turn off engine
2. Allow engine to cool completely if previously running
3. Open hood and locate AC service ports on low and high pressure lines near firewall
4. Verify AC compressor clutch engages when AC is turned on before proceeding (if clutch does not engage, diagnose electrical or compressor issues first)
5. Check for visible signs of refrigerant leaks, damaged lines, or oil residue around fittings

Procedure

1. 1

   Connect recovery machine to service ports
   Remove dust caps from both low-side (larger port, near accumulator) and high-side (smaller port, near compressor discharge line) service ports. Connect the blue hose from manifold gauge set to low-side port and red hose to high-side port. Ensure connections are secure and seated properly.
2. 2

   Recover existing refrigerant
   Start the recovery machine and follow manufacturer instructions to evacuate all refrigerant from the system. The machine will automatically stop when recovery is complete. Note the amount of refrigerant recovered - the system holds approximately 18.5 oz (525g) of R-134a when fully charged. If significantly less was recovered, suspect a leak.
3. 3

   Perform vacuum test
   With recovery complete, switch machine to vacuum mode or connect dedicated vacuum pump. Evacuate the system to at least 29 inches of mercury (98 kPa vacuum) and maintain for minimum 30 minutes. This removes moisture and air from the system. Monitor vacuum gauge - if vacuum does not hold steady, there is a leak that must be repaired before recharging.
4. 4

   Verify system holds vacuum
   After 30-minute vacuum period, close all valves and turn off vacuum pump. Observe vacuum gauge for 10 minutes. Vacuum should remain stable at 29 inches Hg or higher. If vacuum drops more than 2 inches, there is a leak - do not proceed with recharge until leak is found and repaired.
5. 5

   Add refrigerant oil if needed
   If compressor was replaced or significant oil was lost during recovery, add appropriate amount of PAG oil through low-side port using oil injector tool. For routine recharge, add 1-2 oz to replace oil lost during recovery. Use PAG 46 viscosity oil or equivalent specified by Kia.
6. 6

   Recharge system with R-134a
   Connect refrigerant container to recharge machine. Ensure scale is zeroed. Charge system with exactly 18.5 oz (525g) of R-134a refrigerant. Charge through low-side port with engine off initially, then start engine and set AC to MAX/recirculation mode with blower on high to complete charge. Monitor pressure gauges - low side should be 25-35 PSI and high side 200-250 PSI at idle with ambient temperature of 75-85°F.
7. 7

   Check system operation
   With engine running at 1500 RPM and AC on MAX, verify compressor clutch engages and remains engaged. Check that low-side pressure is 25-35 PSI and high-side pressure is 200-250 PSI (values vary with ambient temperature). Feel the low-side line - it should be cold to touch. Check high-side line - it should be hot.
8. 8

   Test cooling performance
   Allow system to run for 5 minutes. Insert thermometer in center dash vent. With outside temperature 70-90°F, vent temperature should be 35-45°F. Temperature difference between ambient and vent should be at least 30-40°F. If cooling is inadequate despite proper pressures, check cabin air filter, blend door operation, or evaporator restrictions.
9. 9

   Disconnect equipment and secure caps
   Turn off engine and AC. Close all valves on manifold gauge set. Carefully disconnect hoses from service ports - expect small amount of refrigerant release. Immediately reinstall dust caps on both service ports and hand-tighten securely to prevent moisture entry and refrigerant loss.

Reassembly

1. No disassembly required for basic recharge procedure
2. Ensure service port caps are installed securely to maintain system seal
3. If any AC line fittings were disconnected during leak repair, torque to 20.0 Nm (15 lb-ft) with new O-rings and appropriate PAG oil on O-rings

Verification

• Start engine and turn AC to MAX with recirculation on and blower at highest speed
• Verify compressor clutch engages within 2-3 seconds and remains engaged
• Confirm center dash vent temperature reaches 35-45°F within 2-3 minutes
• Check that low-side pressure is 25-35 PSI and high-side is 200-250 PSI at idle (ambient temp 75-85°F)
• Listen for unusual noises from compressor - chattering or squealing indicates problems
• Inspect service port areas and all visible fittings for signs of refrigerant leaks (oil residue or frost)
• Test drive vehicle and confirm cooling remains consistent during operation

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