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A/C Refrigerant System (R-134a), Discharging




A/C refrigerant system (R-134a), discharging


WARNING!
- Always use an Underwriter's Laboratory (UL) approved refrigerant recovery/recycling/recharging unit such as Kent-Moore ACR(4), or equivalent, whenever discharging an R-134a A/C system.
- Any person who services a motor vehicle air conditioner MUST, by law, be properly trained and certified and use approved refrigerant recycling equipment. Technicians must complete an EPA approved recycling course to be certified.
- State and local governments may have additional requirements regarding air conditioning servicing. Always comply with state and local laws.
- Always wear safety goggles when discharging, evacuating or recharging an A/C system.


CAUTION!
- Always use separate refrigerant recovery/recycling/recharging servicing equipment for R-12 and R-134a systems. DO NOT use one piece of equipment for both R-12 and R-134a systems. The residual traces of refrigerant inside the equipment will contaminate and damage the equipment. Servicing equipment includes recovery/recycling/recharging unit, charging station, vacuum pump, manifold gauges, etc.
- DO NOT use R-12 servicing equipment on R-134a systems or R-134a equipment on R-12 systems or damage to both the vehicle A/C system and servicing equipment may result. Use only equipment designed to meet Society of Automotive Engineers (SAE) standards.
- R-134a and R-12 systems use different size service fittings. NEVER use adaptors to convert an R-12 fitting to R-134a size or R-134a fitting to R-12 size.



NOTE: Follow all safety measures, when discharging an A/C refrigerant system.

Discharging
Make sure initial set-up has been performed on recovery/recycling/recharging unit before discharging A/C system.






- Connect red high pressure hose -A- of refrigerant recovery/recycling/recharging unit to high pressure service valve (fitting) on vehicle and open coupler valve.
- Leave blue low pressure hose -B- of refrigerant recovery/recycling/recharging unit disconnected.


NOTE:
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 and charging) through the high pressure service valve only.


CAUTION!
Always follow manufacturer's instructions when using refrigerant/recovery/recycling/recharging unit.


- Following refrigerant recovery/recycling/recharging unit manufacturer's instructions, discharge A/C system into refrigerant recovery/recycling/recharging unit.
- After emptying A/C system, disconnect power supply from A/C clutch -N25- (e.g. unplug connector from A/C refrigerant low pressure switch -F73-) to prevent accidental compressor operation with A/C system discharged.