This procedure covers the removal and replacement of the AC accumulator (receiver-drier) on a 2021-2024 Ford F-150 with 3.5L EcoBoost engine, including refrigerant recovery, component replacement, and system recharge.

Warnings

Tools required

Parts

• AC accumulator/receiver-drier assembly × 1 — Use OEM specification for R-134a or R-1234yf system
• AC line O-ring kit × 1 — Use OEM specification matching refrigerant type
• PAG oil (PAG-46 for R-134a or POE oil for R-1234yf) × 1 — Use OEM specification

Fluids

• R-134a or R-1234yf refrigerant (verify system type on underhood label)

Preparation

1. Verify refrigerant type from underhood AC specification label
2. Park vehicle on level surface and engage parking brake
3. Allow engine to cool completely if recently operated
4. Record total refrigerant charge amount from underhood label for recharge reference
5. Ensure AC recovery machine is certified for the refrigerant type in this vehicle
6. Gather new O-rings and correct PAG/POE oil type for system

Procedure

1. 1

   Recover refrigerant from AC system
   Connect AC recovery machine to high and low side service ports. Follow recovery machine instructions to completely evacuate refrigerant from the system. Record the amount recovered for comparison to specification. Verify recovery is complete by monitoring gauge pressures reaching atmospheric levels.
2. 2

   Locate and access the AC accumulator
   The accumulator is mounted on the firewall passenger side near the evaporator. From the engine bay, identify the cylindrical accumulator canister with inlet and outlet refrigerant lines. Remove any plastic engine covers or shields that obstruct access to the accumulator mounting bracket.
3. 3

   Disconnect electrical connector
   Locate the pressure switch connector on top of the accumulator. Press the locking tab and pull the connector straight off the switch. Move the harness aside to prevent damage during removal.
4. 4

   Disconnect AC lines from accumulator
   Using the appropriate AC line disconnect tool, release the spring lock coupling on the inlet line from the evaporator. Similarly disconnect the outlet line to the compressor. Cap or plug the open lines immediately to prevent moisture and debris entry. Inspect the line fittings for damage.
   Torque spec

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

   Remove accumulator mounting hardware
   Remove the mounting bracket bolts securing the accumulator to the firewall using a 10mm socket. Support the accumulator while removing the last bolt to prevent it from falling. Carefully maneuver the accumulator out of the engine bay, noting its orientation for installation reference.
   Torque spec

   Mounting Bracket Bolts28 Nm (21 lb-ft)
6. 6

   Drain and measure old accumulator oil
   Drain the old accumulator into a clean graduated container and measure the oil amount. Note the quantity of oil drained - you will need to add this same amount plus 1 ounce to the new accumulator to compensate for system losses. If debris or metal particles are present in the oil, inspect compressor for damage.
7. 7

   Prepare new accumulator
   Remove the new accumulator from its packaging immediately before installation. Remove the shipping caps from the inlet and outlet ports. Add the measured oil quantity plus 1 ounce of the correct PAG or POE oil (depending on refrigerant type) into the accumulator inlet port. If a new pressure switch was not included, carefully transfer the switch from the old accumulator using a proper wrench to avoid damage.
8. 8

   Install new O-rings on AC lines
   Remove the old O-rings from both AC line connections and discard. Install new O-rings from the kit, ensuring they match the refrigerant type (green for R-1234yf, black for R-134a). Lightly coat the new O-rings with the appropriate PAG or POE oil to ease installation and ensure proper sealing.
9. 9

   Install new accumulator
   Position the new accumulator in the mounting bracket in the same orientation as the old unit. Thread the mounting bracket bolts hand-tight first to ensure proper alignment. Torque the mounting bracket bolts to specification in a cross pattern to prevent distortion.
   Torque spec

   Mounting Bracket Bolts28 Nm (21 lb-ft)
10. 10

    Reconnect AC lines
    Remove caps from AC lines. Push each line fitting into the accumulator ports until the spring lock coupling clicks into place. Gently pull on each line to verify it is fully locked. Torque the AC line fittings to specification.
    Torque spec

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

    Reconnect electrical connector
    Plug the pressure switch electrical connector onto the switch on top of the accumulator. Ensure the connector locks securely and the harness routing does not create strain on the connection.
12. 12

    Evacuate the AC system
    Connect the vacuum pump to the AC service ports through the manifold gauge set. Evacuate the system to at least 500 microns for a minimum of 45 minutes. After evacuation, close valves and monitor for 10 minutes - vacuum should hold steady indicating no leaks. If vacuum rises, there is a leak that must be located and repaired.
13. 13

    Recharge AC system
    Using the charging machine or scale, add the exact refrigerant charge amount specified on the underhood label. Charge through the low-side service port with engine running and AC on maximum cold. Monitor pressures during charging. Do not overcharge - use the exact amount specified by weight, not pressure readings alone.
14. 14

    Leak test the system
    With the system fully charged, use an electronic leak detector to check all connections at the accumulator, including both line fittings and the pressure switch. Also check along the AC line paths. If any leaks are detected, recover refrigerant, repair the leak, and repeat evacuation and recharge procedures.

Reassembly

1. Reinstall any plastic engine covers or shields removed for access
2. Verify all electrical connectors are secured and harnesses properly routed
3. Double-check all AC line connections are tight and leak-free

Verification

• Start engine and set AC to maximum cold and high fan speed
• Verify compressor clutch engages and cycles normally
• Check that vent temperatures reach 38-42°F within 5 minutes at idle
• Monitor high and low side pressures - typical values are 150-250 psi high side and 25-35 psi low side at idle with 75°F ambient temperature
• Verify no unusual noises from compressor or system
• Confirm pressure switch connector shows no fault codes in vehicle diagnostics
• Test AC performance during road test to verify proper cooling under load

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