VALVE AS-CHECK 1302940 - Caterpillar

Adding Additional Refrigerant to an Air Conditioning System that Has a Low Charge
Failure to properly follow the procedure may cause compressor failure. The procedure that follows is not the preferred method for charging an air conditioning system. The preferred method of measuring the refrigerant is by weight.
Note: The procedure that follows is applicable only if the inlet air temperature at the condenser is above 21 °C (70.0 °F). The procedure may be repeated a second time in order to achieve the proper charge with this method.
If the system has no refrigerant, evacuate the system before charging the system. The refrigerant charge should be measured by weight.
Illustration 2 g00896707
(1) Low pressure valve (2) High pressure valve (3) Manifold gauge set (4) Valve on top of refrigerant tank (5) Charging hose (6) Low pressure hose (7) High pressure hose (8) Service valve (discharge) (9) Service valve (suction) (A) Vapor (B) Liquid
Connect the manifold gauge set to the discharge and service ports on the compressor. Refer to Testing and Adjusting, "Manifold Gauge Set (Refrigerant) - Install".
Make sure that the low pressure valve (1) and the high pressure valve (2) are closed on the manifold gauge set (3) .
Turn the valve (4) on the tank counterclockwise. This action will release the refrigerant to the charging hose (5) .Note: Make sure that the cylinder of refrigerant is in the upright position. This allows the refrigerant to enter the system as a gas.
Loosen the hose connection on the charging hose (5) at the manifold gauge set for two to three seconds. Then tighten the connection. This action allows air to be released from the charging hose (5) .
Remove high pressure hose (7) from service valve (8). Quickly place a clean rag over the opening in service valve (8). Open discharge valve (2) about one half turn for two or three seconds. Remove the rag and attach high pressure hose (7) and quickly close discharge valve (2). Repeat the procedure for the low pressure hose (6) .
Start the engine and run the engine at 1300 to 1400 rpm.
Position the temperature control knob to the MAX position, and position the fan switch to the HI position.Note: If the machine is equipped with an expansion valve system, refer to "Expansion Valve System". If the machine is equipped with an Orifice Tube system, refer to "Orifice Tube System".Expansion Valve System
Identify the capacity of the receiver-dryer. The part number is printed on the receiver-dryer.
Table 3
Receiver-Dryer Capacities    
Part Number     Capacity    
9D-6888    
0.5 kg (1 lb)    
8T-8642    
0.9 kg (2 lb)    
5V-5698    
0.9 kg (2 lb)    
9W-0549    
0.9 kg (2 lb)    
106-3532    
0.9 kg (2 lb)    
106-5534    
0.9 kg (2 lb)    
106-5533    
0.9 kg (2 lb)    
Open suction valve (1) in order to release the refrigerant into low pressure hose (6). Slowly add refrigerant until the bubbles disappear in the sight glass. After the bubbles disappear, add the proper amount of refrigerant for the