Heating and Air Conditioning: Service Precautions

WARNING: Should refrigerant HFC-134a (R-134a) strike your eye(s), consult a doctor immediately.
- DO NOT USE YOUR HAND TO RUB AFFECTED EYE(S).
Instead, use quantities of fresh cold water to splash it over affected area to thus gradually raise its temperature above the freezing point.
- Obtain proper treatment as soon as possible from a doctor or eye specialist.
Should liquid refrigerant HFC-134a (R-134a) get on your skin, such affected part should be treated in the same manner as when skin is frostbitten or frozen.

CAUTION: None of refrigerant, compressor oil and component parts is interchangeable between two types of A/C: one using CFC-12 (R-12) and the other using HFC-134a (R-134a).
(For identification between these two types.
When replenishing or changing refrigerant and compressor oil and when replacing parts, make sure that the material or the part to be used is appropriate to the A/C installed in the vehicle being serviced.
Use of incorrect one will result in leakage of refrigerant, damage in parts or other faulty condition.

PRECAUTION
When servicing air conditioning system, the following rules must be observed.

PIPING
- When connecting hoses and pipes, apply a few drops of compressor oil (refrigerant oil) to seats of coupling nuts and O-ring.

Piping:

- Never use heat for bending pipes. When bending a pipe try to make its bending radius as slight as possible.
- Keep internal parts of air conditioning free from moisture and dirt. When disconnecting any line from system, install a blind plug or cap to the fitting immediately.
- When tightening or loosening a fitting, use two wrenches, one for turning and the other for support.
- Tighten flared nuts to specified torque.

Tightening torque
8 mm pipe : 13 N.m (1.3 kg-m, 9.5 lb-ft)
14.5 mm pipe : 23 N.m (2.3 kg-m, 16.6 lb-ft)
16 mm pipe : 33 N.m (3.3 kg-m, 23.8 lb-ft)

- Route drain hose so that drained water does not make any contact to vehicle components.

HANDLING REFRIGERANT HFC-134a (R-134a)
- When handling refrigerant, always wear goggles to protect your eyes.
- Avoid you direct contact to liquid refrigerant.
- Do not heat refrigerant container higher than 40 °C (104 °F).
- Do not discharge refrigerant into atmosphere.
- Do not allow liquid refrigerant to touch bright metals. Refrigerant combined with moisture is corrosive and will tarnish surfaces of bright metals including chrome.
- After recovering refrigerant from system, the amount of compressor oil removed must be measured and the same amount added to the system.

REFRIGERANT RECOVERY
When discharging refrigerant out of A/C system, always recover it by using refrigerant recovery and recycling equipment. Discharging refrigerant HFC-134a (R-134a) into atmosphere would cause adverse effect to environments.

NOTE: When handling recovery and recycling equipment, be sure to follow the instruction manual for the equipment.

REFRIGERANT CHARGE
Charge a proper amount of refrigerant to A/C system according to charging procedure described in recovery, evacuation and charging.

CAUTION: Do not perform an additional refrigerant charging to A/C system. This cause it to overcharge.