COUPLING AS 6V4657 - Caterpillar

Personal injury can result from contact with refrigerant.This system is under pressure at all times, even if the engine is not running. Heat should never be applied to a charged system.Contact with refrigerant can cause frost bite. Keep face and hands away to help prevent injury.Protective goggles must always be worn when refrigerant lines are opened, even if the gauges indicate the system is empty of refrigerant.Always use caution when a fitting is removed. Slowly loosen the fitting. If the system is still under pressure, evacuate the system recovering the refrigerant before removing the fitting.Personal injury or death can result from inhaling refrigerant through a lit cigarette.Inhaling air conditioner refrigerant gas through a lit cigarette or other smoking method or inhaling fumes released from a flame contacting air conditioner refrigerant gas, can cause bodily harm or death.Do not smoke when servicing air conditioners or wherever refrigerant gas may be present.Before any checks of the air conditioning and heating system are made, move the machine to a smooth horizontal surface. Lower all implements to the ground. Make sure the transmission is in neutral or park and that the parking brake is engaged. Keep all other personnel away from the machine or where they can be seen.
Illustration 1 g00470944
(1) Low pressure valve
(2) High pressure valve
(3) Low pressure hose
(4) High pressure hose
(5) Service valve (low pressure side)
(6) Charging hose
(8) Service valve (high pressure side)
(9) Manifold gauge set
(R) Recovery station
Connect manifold gauge set (9) to the service valves near the refrigerant compressor. The service valves for charging are located on the refrigerant lines. Connect low pressure hose (3) to service valve (5) on the suction side of the compressor. Connect high pressure hose (4) to service valve (8) on the discharge side of the compressor. Make sure that the valved couplings are turned counterclockwise for installation.
Turn the pressure valves clockwise and make sure that both pressure valves on the manifold gauge set are closed.
Put a clean cloth over the disconnected charging hose fitting at the manifold gauge set. This will prevent the spraying of compressor oil. Open low pressure valve (1) on manifold gauge set (9) about 1/2 turn. Keep the valve open for 2 to 3 seconds in order to release air from the hose. This will also release air from the gauge set. Close low pressure valve (1) on the gauge set. Repeat this process for high pressure valve (2).
Tighten the charging hose fitting at manifold gauge set (9). Note: Use a refrigerant identifier (analyzer) in order to prevent refrigerant that is not R-134a from contaminating tools.