This procedure replaces the AC expansion valve (TXV) on a 2015 Kia Forte 1.8L, requiring refrigerant recovery, removal of AC lines, and installation of a new valve with proper torque specifications and system recharge.

Warnings

Tools required

Parts

• AC Expansion Valve (TXV) × 1 — Use OEM specification
• AC Line O-rings (multiple sizes) × 1 — Use OEM specification
• R-134a Refrigerant × 1 — Typically 16-20 oz total system capacity
• PAG Oil (ND-11 or equivalent) × 1 — Use OEM specification
• AC System UV Dye (optional) × 1 — Compatible with R-134a

Preparation

1. Park vehicle on level ground and engage parking brake
2. Allow engine to cool completely if recently operated
3. Verify AC system refrigerant type using identifier tool (should be R-134a)
4. Gather all replacement parts, tools, and new O-rings before beginning
5. Ensure AC recovery machine is certified and operational

Procedure

1. 1

   Recover AC refrigerant
   Connect AC recovery machine to service ports. Follow machine manufacturer instructions to completely recover all refrigerant from the system. Record the amount of refrigerant and oil recovered for proper refill quantities. Verify system pressure is at 0 PSI before proceeding.
2. 2

   Access expansion valve location
   The expansion valve is located at the evaporator inlet, typically near the firewall on the passenger side. Remove the engine cover if equipped. Remove any necessary trim panels or components blocking access to the firewall area where AC lines enter the cabin. You may need to remove the battery or air intake components for better access.
3. 3

   Disconnect AC lines from expansion valve
   Using flare nut wrenches to prevent rounding, carefully loosen and remove the AC line fittings connected to the expansion valve. The valve typically has two connections: one from the condenser (high pressure liquid line) and one to the evaporator. Cap or plug all open fittings immediately to prevent moisture and contamination from entering the system. Inspect the removed lines for debris or metal particles.
4. 4

   Remove old expansion valve
   Remove the mounting bolts or screws securing the expansion valve to the evaporator or mounting bracket. Carefully extract the old expansion valve, noting its orientation and position. Remove and discard all old O-rings from the valve seats and AC line connections. Inspect the evaporator inlet for any debris or blockage.
5. 5

   Prepare new expansion valve
   Remove the new expansion valve from packaging. Verify it matches the old valve exactly. Install new O-rings on all connection points, lubricating each O-ring with a small amount of clean PAG oil (ND-11). Ensure O-rings are properly seated in their grooves without twisting or pinching. Add approximately 1-2 ml of fresh PAG oil to the valve inlet to replace oil lost during service.
6. 6

   Install new expansion valve
   Position the new expansion valve in the correct orientation (ensure the sensing bulb, if external, is properly positioned). Install mounting bolts or screws finger-tight first to ensure proper alignment. Torque the expansion valve mounting fasteners to specification.
   Torque spec

   Expansion Valve10 Nm (7 lb-ft)
7. 7

   Reconnect AC lines
   Install new lubricated O-rings on all AC line fittings. Add a small amount of PAG oil to each O-ring. Carefully thread the AC line fittings onto the expansion valve by hand to avoid cross-threading. Use flare nut wrenches to torque fittings to specification. Do not over-tighten as this can damage the O-rings and cause leaks.
   Torque spec

   AC Line Fittings20 Nm (15 lb-ft)
8. 8

   Reinstall removed components
   Reinstall any trim panels, air intake components, battery, or engine covers that were removed for access. Ensure all fasteners are properly secured and no tools or parts are left in the engine bay.
9. 9

   Evacuate AC system
   Connect AC vacuum pump to service ports. Evacuate the system to at least 29 inches Hg (98 kPa) vacuum. Maintain vacuum for minimum 30 minutes, preferably 45-60 minutes to remove all moisture. Monitor vacuum gauge for any pressure rise that would indicate a leak. If vacuum holds steady, system is ready for recharge.
10. 10

    Recharge AC system
    With vacuum pump still running, close service valves and disconnect vacuum pump. Connect refrigerant source to low-side service port. Add the proper amount of R-134a refrigerant (typically 16-20 oz total - consult underhood label for exact specification). If UV dye was not pre-mixed, add appropriate amount during charging. Charge liquid refrigerant into low side with engine off, then start engine and set AC to maximum cold and high fan speed. Complete charging on low side with vapor refrigerant as needed to achieve proper pressures.
11. 11

    Verify system operation
    With engine running and AC on maximum, monitor high and low side pressures using manifold gauges. Typical pressures at 80°F ambient: low side 25-35 PSI, high side 200-250 PSI (pressures vary with ambient temperature). Check center vent temperature with digital thermometer - should achieve 40-50°F at maximum cooling. Verify compressor clutch engages and cycles properly. Listen for any unusual noises from the compressor or expansion valve.

Reassembly

1. Ensure all AC line fittings are torqued to specification and not leaking
2. Verify all access panels and components are reinstalled properly
3. Double-check that no tools or rags were left in engine compartment

Verification

• Start engine and run AC system at maximum cooling for 10-15 minutes
• Verify center vent temperature reaches 40-50°F with digital thermometer
• Check all AC line connections for leaks using electronic leak detector or UV light if dye was added
• Monitor AC pressures with manifold gauges to confirm proper system operation
• Verify compressor clutch engages smoothly without excessive cycling
• Listen for proper expansion valve operation (slight hissing at evaporator is normal)
• Test AC system performance in recirculation and fresh air modes
• Confirm no refrigerant odor in cabin and proper airflow from all vents

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