AC Recharge

This procedure evacuates the existing refrigerant from the AC system, checks for leaks, and recharges the system with the proper amount of R-134a refrigerant and PAG oil for optimal cooling performance.

Warnings

Tools required

Parts

• R-134a refrigerant × 1 — Approximately 16-18 oz total capacity
• PAG oil (ND-11) × 1 — Honda ND-11 or equivalent PAG 46
• AC service port caps × 2 — Replace if damaged

Preparation

1. Park vehicle on level ground and turn off engine. Allow AC system to stabilize to ambient temperature if recently operated.
2. Verify VIN to confirm 2018-2024 Honda Accord with 1.5L turbo engine (engine code L15B7).
3. Locate AC service ports: Low-pressure port on larger suction line near firewall, high-pressure port on smaller liquid line near condenser.
4. Ensure AC recovery machine is properly set up and turned on according to manufacturer instructions.
5. Have Material Safety Data Sheet (MSDS) for R-134a available.

Procedure

1. 1

   Connect manifold gauges
   Remove dust caps from both AC service ports. Connect blue (low-pressure) hose to the low-pressure service port on the larger suction line. Connect red (high-pressure) hose to the high-pressure service port on the smaller liquid line. Ensure connections are secure but do not overtighten. Keep both manifold gauge valves closed at this time.
2. 2

   Record initial system pressure
   With engine off, observe both gauge readings. A properly charged static system should show approximately 70-90 psi depending on ambient temperature. If pressure is near zero, there is likely a leak that must be repaired before recharging. If pressure is significantly high (over 150 psi static), do not proceed until system is inspected.
3. 3

   Recover existing refrigerant
   Connect the center yellow hose from manifold gauge set to the AC recovery machine inlet. Start the recovery machine and follow manufacturer procedures. Open both high and low-pressure valves on the manifold gauge set slowly. Allow the recovery machine to extract all refrigerant from the system. This typically takes 5-10 minutes. Once recovery is complete and gauges show vacuum, close both manifold valves and turn off recovery machine.
4. 4

   Perform vacuum test
   Disconnect recovery machine and connect AC vacuum pump to the center yellow hose. Open both manifold gauge valves. Start vacuum pump and evacuate system for minimum 30 minutes. Both gauges should read 29-30 inches of vacuum (approximately -29 to -30 inHg). After 30 minutes, close both manifold valves and turn off vacuum pump. Observe gauges for 10 minutes - vacuum should hold steady, indicating no leaks.
5. 5

   Check for leaks
   If vacuum does not hold and pressure rises back toward zero, there is a leak in the system. Use electronic leak detector or UV dye to locate leak source. Common leak points include compressor shaft seal, condenser, evaporator, and line fittings. Any leaks must be repaired before proceeding with recharge. Re-evacuate system after repairs.
6. 6

   Add PAG oil if needed
   If any major components were replaced or if more than 2 oz of oil came out during recovery, add appropriate amount of Honda ND-11 PAG oil through the low-pressure service port. For recharge-only service with no component replacement, typically no additional oil is needed. Refer to Honda service manual for specific oil quantities if components were replaced.
7. 7

   Prepare refrigerant charge
   Place R-134a refrigerant canister on digital scale and record starting weight. The 2018-2024 Honda Accord 1.5L turbo requires approximately 16-18 oz (450-510 grams) of R-134a total capacity. Verify exact specification on the underhood AC specification label. Connect refrigerant canister to center yellow hose on manifold gauge set.
8. 8

   Charge system with engine off
   Open valve on refrigerant canister. Slowly open the low-pressure (blue) valve on manifold gauge set. Allow refrigerant to flow into system by vapor pressure alone. Monitor scale weight. Add approximately half the total required charge (8-9 oz) in this manner. This may take 3-5 minutes. Close low-pressure valve when target amount is reached.
9. 9

   Complete charge with engine running
   Start engine and set AC controls to MAX cooling, recirculation mode, fan on HIGH, temperature to coldest setting. Engine should be at idle (approximately 700-800 RPM). Slowly open low-pressure valve on manifold gauge set to continue adding refrigerant. Monitor both gauges and scale weight. Low-pressure gauge should read 25-35 psi, high-pressure gauge should read 200-250 psi with engine running at idle and ambient temperature around 75-85°F. Add remaining refrigerant until total system capacity is reached based on scale measurement.
10. 10

    Verify system operation
    With system fully charged and running, verify proper operation. Low-pressure reading should be 25-35 psi, high-pressure reading 200-250 psi at idle with ambient temperature 75-85°F (readings vary with ambient temperature). Compressor should cycle on and remain engaged. Center dash vents should produce air temperature of 40-50°F. If readings are abnormal, recover refrigerant and inspect system for issues.
11. 11

    Disconnect equipment
    Close refrigerant canister valve. Close both manifold gauge valves. Turn off engine and AC. Quickly disconnect low-pressure hose from service port, then high-pressure hose. Some refrigerant loss during disconnection is normal (minimal loss). Immediately install service port caps on both ports to prevent contamination and seal system.

Reassembly

1. Ensure both AC service port caps are securely installed to maintain system cleanliness and prevent moisture entry.
2. Store all AC service equipment properly and ensure refrigerant canisters are sealed.
3. Document the amount of refrigerant and oil added for future service reference.

Verification

• Start engine and run AC system on MAX cooling for 5 minutes. Center dash vents should produce air temperature between 40-50°F measured with thermometer.
• Verify compressor clutch engages and remains engaged during operation. Listen for unusual noises from compressor.
• Check all AC line connections and service ports for signs of oil leakage indicating refrigerant leak.
• Confirm both cooling fans operate when AC is on and system reaches appropriate pressure.
• Test AC performance during short test drive under various load conditions to ensure consistent cooling.

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