This procedure covers the replacement of the AC hose assembly on a 2016-2024 Hyundai Tucson with the 2.5L I4 engine, including refrigerant recovery, hose removal, installation with new O-rings, and system recharge.

Warnings

Tools required

Parts

• AC hose assembly (specify suction or discharge) × 1 — Use OEM specification
• AC O-ring kit × 1 — Use OEM specification
• R-134a refrigerant × 1 — Use OEM specification
• PAG 46 compressor oil × 1 — Use OEM specification

Preparation

1. Verify AC system is not operating and engine is off
2. Park vehicle on level surface and engage parking brake
3. Allow engine to cool completely if recently operated
4. Disconnect negative battery terminal and wait 3 minutes for airbag system discharge
5. Remove engine splash shield (if equipped) for access to lower AC lines
6. Identify which AC hose requires replacement (suction or discharge line)

Procedure

1. 1

   Recover refrigerant from AC system
   Connect refrigerant recovery machine to both high and low side service ports. Follow machine manufacturer instructions to fully recover all R-134a refrigerant from the system. Record the amount of refrigerant and oil recovered for recharge reference. Ensure system shows 0 psi on both sides before proceeding.
2. 2

   Remove engine cover and air intake components
   Remove the upper engine cover by pulling upward on the retaining clips. Loosen the air intake duct clamp at the throttle body and mass air flow sensor. Remove the air filter box and intake duct assembly to provide access to the AC lines in the engine bay. Set components aside in clean area.
3. 3

   Disconnect AC line from condenser
   Locate the AC hose connection at the condenser (front of vehicle, near radiator). Clean the connection area thoroughly with shop towels. Using appropriate size wrench, loosen and remove the AC line fitting bolt. Immediately cap both openings with clean plugs or tape to prevent moisture and debris entry. Remove and discard the old O-rings.
   ⚠Small amount of residual refrigerant or oil may escape. Wear safety glasses and avoid breathing vapors.
   Torque spec

   AC Line Fittings20 Nm (15 lb-ft)
4. 4

   Disconnect AC line from evaporator or compressor
   Locate the opposite end of the AC hose assembly at either the evaporator (firewall area) or compressor (lower engine). For discharge line: disconnect at compressor. For suction line: disconnect at evaporator inlet. Remove the line fitting bolt and separate the connection. Cap all openings immediately. Remove and discard old O-rings.
   ℹ️For discharge line at compressor, note the orientation of the fitting for proper reinstallation.
   Torque spec

   AC Line Fittings20 Nm (15 lb-ft)
5. 5

   Remove hose mounting brackets
   Trace the AC hose routing and locate all mounting brackets and clips. Remove mounting bolts securing the hose assembly to the engine bay or chassis. There are typically 2-3 mounting points depending on which hose is being replaced. Keep hardware organized for reinstallation.
   Torque spec

   Mounting Bolts27 Nm (20 lb-ft)
6. 6

   Remove old AC hose assembly
   Carefully maneuver the old AC hose assembly out of the engine bay, noting the exact routing path. Take photos if necessary to document routing around other components. Inspect the removed hose for signs of damage, abrasion, or leak points to confirm failure location.
7. 7

   Prepare new AC hose assembly
   Unpack new AC hose assembly and verify it matches the old hose configuration. Install new O-rings (included in kit) onto both ends of the new hose. Coat each O-ring with fresh PAG 46 oil - use approximately 5ml of oil per O-ring. Ensure O-rings are properly seated in their grooves. Keep fittings capped until ready to install.
   ⚠Use only PAG 46 oil specified for R-134a systems. Do not use mineral oil or wrong PAG viscosity.
8. 8

   Route new AC hose assembly
   Following the documented routing path, carefully position the new AC hose assembly in the engine bay. Ensure the hose does not contact any sharp edges, hot engine components, or moving parts. Verify adequate clearance from accessory drive belt, cooling fans, and exhaust manifold. Do not remove caps from fittings yet.
9. 9

   Install hose mounting brackets
   Secure the AC hose assembly to all mounting points using the original brackets and bolts. Torque mounting bolts to specification. Ensure the hose is properly supported along its entire length with no stress on the end fittings. Verify the hose routing maintains clearance from moving and hot components.
   Torque spec

   Mounting Bolts27 Nm (20 lb-ft)
10. 10

    Connect AC line to evaporator or compressor
    Remove cap from the first connection point (evaporator or compressor). Verify the O-ring is properly positioned and lubricated. Insert the fitting straight into the mating connection - do not cross-thread. Hand-tighten the line fitting bolt, then torque to specification using a torque wrench. Do not over-tighten as this can damage O-rings.
    ⚠Ensure fitting is aligned properly before tightening. Cross-threading aluminum fittings will require component replacement.
    Torque spec

    AC Line Fittings20 Nm (15 lb-ft)
11. 11

    Connect AC line to condenser
    Remove cap from the condenser end of the new hose assembly. Verify O-ring condition and lubrication. Connect the fitting to the condenser, ensuring proper alignment. Hand-tighten the AC line fitting bolt, then torque to specification. Double-check that both connections are secure and O-rings have not been displaced during installation.
    Torque spec

    AC Line Fittings20 Nm (15 lb-ft)
12. 12

    Evacuate AC system
    Connect vacuum pump to both service ports using manifold gauge set. Open both valves and evacuate the system to at least 29 inches of mercury vacuum. Hold vacuum for minimum 30 minutes (45 minutes recommended) to remove all air and moisture. Monitor for vacuum loss which would indicate a leak. If vacuum holds steady, system is ready for recharge.
    ⚠Inadequate evacuation will leave moisture in system causing poor performance and compressor damage.
13. 13

    Recharge AC system
    With vacuum pump isolated, charge the system with the recorded amount of R-134a refrigerant (typically 500-550 grams for this system, verify on underhood label). Add refrigerant oil if total recovered was less than expected (typically 50-80ml total system capacity). Use refrigerant scale for accurate charging. Start engine and verify compressor engagement. Monitor gauge pressures for proper operation.
    ℹ️Typical system pressures: Low side 25-35 psi, High side 225-275 psi at idle with ambient temp 70-80°F.
14. 14

    Leak test and final inspection
    Using electronic leak detector or UV dye method, check all connections for refrigerant leaks. Pay special attention to both AC line fittings. Run AC system at maximum cooling for 10 minutes and recheck all connections. Verify cold air output from dash vents. Check that AC hose does not contact any components during engine operation.

Reassembly

1. Reinstall air intake duct and air filter box assembly, ensuring all clamps are properly tightened
2. Install engine cover by aligning clips and pressing down firmly until seated
3. Reinstall engine splash shield if removed, ensuring all clips and fasteners are secure
4. Reconnect negative battery terminal and tighten securely
5. Reset clock and radio presets if needed

Verification

• Start engine and turn AC system to maximum cooling with fan on high
• Verify compressor clutch engages (audible click and gauge pressure change)
• Confirm cold air output from dash vents reaches approximately 40-45°F with ambient temp 70-80°F
• Monitor system pressures: Low side should be 25-35 psi, high side 225-275 psi at idle
• Verify no unusual noises from compressor or AC lines during operation
• Check for refrigerant leaks at both AC line connections using leak detector
• Confirm AC hose has adequate clearance from all moving parts with engine running
• Test AC performance during road test under various conditions

More procedures for this vehicle