Heating and Air Conditioning: Fundamentals and Basics

CAUTION:
- Keep work area and all tools clean.
- Use only tools, equipment and parts specified for use with R-134a.
- Always wear protective glasses and gloves when working on A/C refrigerant system.
- Switch on existing exhaust/ventilation systems when working on the refrigerant system.
- Discharge A/C system before removing any A/C refrigerant system component.
- Always use an Underwriters Laboratory (UL) approved refrigerant recovery/ recycling/recharging unit such as Kent-Moore ACR4, or equivalent, whenever discharging an R-134a A/C system.
- Immediately plug open connections on A/C components to prevent dirt and moisture contamination. Likewise, DO NOT remove new component from packaging until ready to install. Immediately tighten component connections after installation.
- Always replace O-rings, DO NOT reuse Use only the correct size and type of O-rings specified for use with R-134a refrigerant. Lubricate O-ring with refrigerant oil before installing
- Use only the specified PAG oil from a sealed container and ALWAYS reseal oil container immediately after use. DO NOT use oil if it has become contaminated with moisture or if oil container has been left open.
- Always reinstall cap(s) over A/C service valve(s).
- DO NOT flush refrigerant system with R-11.
- Evacuate refrigerant system for a minimum of 30 minutes.
- After system recharge, manually rotate A/C compressor approx. 10 turns before starting engine. Start engine with A/C OFF After idle speed has stabilized, switch A/C ON and let engine idle (compressor running) for a minimum of two minutes before raising engine speed.
- DO NOT top-off a charged refrigerant system. Instead, discharge, evacuate and recharge system.

NOTE:
- For information on A/C wiring see applicable wiring diagram.
- See also A/C refrigerant system safety measures. Service Precautions
- Green label in engine compartment indicates A/C system is charged with refrigerant R-134a.
- Only a high pressure service valve is used for A/C system servicing. A low pressure service valve is not installed in the A/C system. Perform all A/C system service operations (i.e discharging, evacuating, recharging) through the high pressure service valve only