Heater And Air Conditioning System Precautions

Before you have opened the systemor locking nut screw tap assembly into adapter so
Bewaresealing gasket is fully seated against the can top.
When discharging air conditioning system, use onlyTurn tap inward to pierce the can and close the
approved refrigerant recovery recyclingtap. DO NOT open tap until ready to purge the
equipment make sure you make every attemptservice hose or dispense refrigerant into the
to avoid discharging refrigerant into thesystem.
atmosphere.Be certain tap handle is turned fully inward to the
DISCHARGING THE A/C SYSTEMclosed position. Check that locking base is turned
The EPA indicates that R-11, R-12 and R-113 areto its outer limit. Securely engage locking lugs
very harmful to the Earths Ozone layer. Makeover the can flange. Turn entire tap assembly
sure you make every attempt possible to avoiddownward into the locking base to pierce the can.
discharging R-11, R-12 or R-113 into theDO NOT open tap until ready to dispense into
atmosphere.system.
1. Remove service valve and install gauges. ForDO NOT open high side hand valve while air
high side gauge hose, Adapter must be used toconditioning system is in operation. This high
connect to high side service valve.pressure could rupture can or fitting at safety can
2. Slightly open low side gauge valve and letvalve, resulting in damage and personal injury.
refrigerant escape slowly without loosingCONNECTING LINES & FITTINGS
refrigerant oil.A new "O" ring should be used in all instances
3. When system is nearly discharged, usingwhen connecting lines and fittings. Always use two
approved refrigerant recovery recyclingwrenches to avoid twisting or distorting lines and
equipment, open high side gauge valve to releasefittings, tighten coupling nuts securely.
any pressure trapped in compressor. Close valvesPLACING SYSTEM IN OPERATION
immediately after discharging to prevent entry of1. Evacuate the system using a vacuum pump.
moisture.2. Charge the system with new R-12 according to
DISCONNECTING LINES & FITTINGSeach individual vehicle to Refrigerant Capacity.
1. After system is discharged, using approved3. Leak test the system, with particular attention
refrigerant recovery recycling equipment, carefullyto all new connections and components.
clean entire area around coupling nut to prevent4. Make a performance test of the system.
dirt entering system. Always use two wrenchesCOMPRESSOR REMOVAL INFORMATION
to avoid twisting or distorting lines and fittingsOn systems which have compressors equipped
2. Cap or plug all LINES and FITTINGSwith stem-type service valves, it is possible to
immediately to prevent entry of air and moistureisolate the compressor for removal.
into system. Do not remove these caps untilTurn both high and low pressure manual valves to
connections are being made make sure you makeextreme clockwise position. Loosen cap on high
every attempt to avoid discharging refrigerantpressure manual valve connection to compressor
into the atmosphere.and allow gas to escape until compressor is
COMPONENT REPLACEMENTrelieved of pressure.
When components are replaced, system oil levelCOMPRESSOR REMOVAL INFORMATION -
must be adjusted. Add refrigeration oil toDISCHARGE METHOD
replacement component. See Compressor oilThis procedure is to be used on vehicles which
Check article, as well as, Component Oilhave compressor equipped with Schrader valves.
Replacement Quantities" chart under "A/CIn these cases, the compressor cannot be
SYSTEM SPECS" article in this HEATER AND AIRisolated and the system must be discharged, using
CONDITIONINGapproved refrigerant recycling equipment.
SYSTEM PRECAUTIONSUSING R-12 REFRIGERANT.
Before you have opened the system1. Always wear eye protection when around air
BE AWAREconditioning systems and R-12. The system's high
When discharging air conditioning system, use onlypressure can cause severe injury to eyes and
approved refrigerant recovery recyclingskin if a hose were to burst. R-12 evaporates
equipment make sure you make every attemptquickly when exposed to atmosphere, freezing
to avoid discharging refrigerant into theanything it contacts.
atmosphere.2. Use care when handling refrigerant containers.
DISCHARGING THE A/C SYSTEMDO NOT drop or strike containers or expose
The EPA indicates that R-11, R-12 and R-113 arerefrigerant containers to excessive heat.
very harmful to the Earths Ozone layer. MakeContainers must never be heated more than
sure you make every attempt possible to avoid(52°C) 125°F. Never expose R-12
discharging R-11, R-12 or R-113 into thedirectly to open flame.
atmosphere.CAUTION: When R-12 is exposed to an open
1. Remove service valve and install gauges. Forflame, drawn into a running engine, or detected
high side gauge hose, Adapter must be used towith a Halide leak tester, poisonous phosgene gas
connect to high side service valve.is formed. Keep work areas ventilated.
2. Slightly open low side gauge valve and letINDIVIDUAL R-12 CANS
refrigerant escape slowly without losing refrigerantDisposable refrigerant cans have a flat type seal
oil.or a screw type seal, and proper can tap must
3. When system is nearly discharged, usingbe used for each type. Be sure sealing gasket on
approved refrigerant recovery recyclingcan tap is in good condition. A proper safety can
equipment, open high side gauge valve to releasetap will prevent refrigerant from flowing back into
any pressure trapped in compressor. Close valvesopen can, as tap has a one-way flow control.
immediately after discharging to prevent entry ofMULTI-CAN DISPENSING VALVES
moisture.A multi-can dispensing valve allows attachment of
DISCONNECTING LINES & FITTINGSseveral cans of refrigerant, and is a good
1. After system is discharged, using approvedsubstitute when a bulk container is not available
refrigerant recovery recycling equipment, carefullyeach leg has its own can tap cans are installed
clean entire area around coupling nut to preventonto each leg of multi-can dispensing valve in the
dirt entering system. Always use two wrenchessame manner as the individual cans.
to avoid twisting or distorting lines and fittingsCAN TAP INSTALLATION FLAT TYPE SEAL
2. Cap or plug all LINES and FITTINGSCANS
immediately to prevent entry of air and moistureRecent findings by the EPA indicate that
into system. Do not remove these caps untilrefrigerant is harmful to the Earth's protective
connections are being made make sure you makeOzone layer. When discharging refrigerant avoid
every attempt to avoid discharging refrigerantallowing refrigerant to enter the atmosphere.
into the atmosphere.Refrigerant recovery system should be used
COMPONENT REPLACEMENTwhen discharging the system.
When components are replaced, system oil levelFirst turn the handle outward to the fully open
must be adjusted. Add refrigeration oil toposition. Securely engage locking lugs over the can
replacement component. See Mercedes oil Checkflange, and lock them in place by turning cam lock
article, as well as, Component Oil Replacementor locking nut. Screw tap assembly into adapter
Quantities chart under "A/C SYSTEM SPECS"so sealing gasket is fully seated against the top.
article in this section.Turn tap inward to pierce the can and close the
USING R-12 REFRIGERANT.tap. DO NOT open tap until ready to purge the
1. Always wear eye protection when around airservice hose or dispense refrigerant into the
conditioning systemsair conditioning systems andsystem.
R-12. The system's high pressure can causeBe certain tap handle is turned fully inward to the
severe injury to eyes and skin if a hose were toclosed position. Check that locking base is turned
burst. R-12 evaporates quickly when exposed toto its outer limit. Securely engage locking lugs
atmosphere, freezing anything it contacts.over the can flange. Turn entire tap assembly
2. Use care when handling refrigerant containers.downward into the locking base to pierce the can.
DO NOT drop or strike containers or exposeDO NOT open tap until ready to dispense into
refrigerant containers to excessive heat.system.
Containers must never be heated more thanDO NOT open high side hand valve while air
(52°C) 125°F. Never expose R-12conditioning system is in operation. This high
directly to open flame.pressure could rupture can or fitting at safety can
CAUTION: When R-12 is exposed to an openvalve, resulting in damage and personal injury.
flame, drawn into a running engine, or detectedCONNECTING LINES & FITTINGS
with a Halide leak tester, poisonous phosgene gasA new "O" ring should be used in all instances
is formed. Keep work areas ventilated.when connecting lines and fittings. Always use two
INDIVIDUAL R-12 CANSwrenches to avoid twisting or distorting lines and
Disposable refrigerant cans have a flat type sealfittings, tighten coupling nuts securely.
or a screw type seal, and proper can tap mustPLACING SYSTEM IN OPERATION
be used for each type. Be sure sealing gasket on1. Evacuate the system using a vacuum pump.
can tap is in good condition. A proper safety can2. Charge the system with new R-12 according to
tap will prevent refrigerant from flowing back intoeach individual vehicle to Refrigerant Capacity.
open can, as tap has a one-way flow control.3. Leak test the system, with particular attention
MULTI-CAN DISPENSING VALVESto all new connections and components.
A multi-can dispensing valve allows attachment of4. Make a performance test of the system.
several cans of refrigerant, and is a goodCOMPRESSOR REMOVAL INFORMATION
substitute when a bulk container is not availableOn systems which have compressors equipped
each leg has its own can tap cans are installedwith stem-type service valves, it is possible to
onto each leg of multi-can dispensing valve in theisolate the compressor for removal.
same manner as the individual cans.Turn both high and low pressure manual valves to
CAN TAP INSTALLATION FLAT TYPE SEALextreme clockwise position. Loosen cap on high
CANSpressure manual valve connection to compressor
Recent findings by the EPA indicate thatand allow gas to escape until compressor is
refrigerant is harmful to the Earth's protectiverelieved of pressure.
Ozone layer. When discharging refrigerant avoidCOMPRESSOR REMOVAL INFORMATION -
allowing refrigerant to enter the atmosphere.DISCHARGE METHOD
Refrigerant recovery system should be usedThis procedure is to be used on vehicles which
when discharging the system.have compressor equipped with Schrader valves.
First turn the handle outward to the fully openIn these cases, the compressor cannot be
position. Securely engage locking lugs over the canisolated and the system must be discharged, using
flange, and lock them in place by turning cam lockapproved refrigerant recycling equipment.