System Leak Check And Evacuation - Trane Thermo King V-520 RT SPECTRUM 50 Installation Manual

Solenoid Valve Positions
IMPORTANT: The Liquid Injection Solenoid Valve, Liquid Solenoid
Valves and the Defrost Solenoid Valve must be in the OPEN position
during evacuation procedures. The valves are normally in the closed
position and must be held open manually using special magnets
(204-1074) designed for this purpose. DO NOT put a magnet onto the
Condenser Blocking Solenoid Valve as this is a normally open valve and
a magnet will close it.
Refrigeration System Evacuation Procedure
1. Connect the Evacuation Station
• 3 Point Evacuation for Model 10 and Model 30 Single
Compressor Applications - Connect the three evacuation lines
from the Evacuation Station to the Discharge Service Valve,
Suction Service Valve and the Service Valve located on the
refrigerant line from the Oil Separator.
• 4 point Evacuation for Model 20 and Model 50 Standby
Compressor Applications - Connect the three evacuation lines
from the Evacuation Station to the Discharge Service Valve,
Suction Service Valve and the Service Line (Yellow) of a gauge set.
Connect the Gauge Set Discharge Line (Red) to the Service Valve
located on the refrigerant line from the Oil Separator. Connect the
Gauge Set Suction Line (Blue) to the Service Valve previously
installed on the standby compressor discharge line from the
Standby Compressor to the Oil Separator.
2. Remove the retaining nut and coil from the normally closed Liquid
Injection Solenoid located near the drier in the Condenser Section.
Install a valve magnet on the valve stem. When the magnet is installed,
a click should be heard as the valve opens.

System Leak Check and Evacuation

IMPORTANT: Do not install a valve magnet on the Condenser Block Off
Solenoid (if present). The condenser block off Solenoid is a normally
open solenoid - installing a valve magnet will close the solenoid.
3. Remove the coil from the normally closed Defrost Solenoid located in
the Evaporator section. When the magnet is installed, a click should be
heard as the valve opens.
4. Open the gauge manifold and vacuum pump valves. Start the vacuum
pump and pump the system down to 500 microns. Continue to pump
for 1 hr. after reaching 500 microns.
IMPORTANT: If the system will not pump down to 500 microns, there is
likely a leak in the system or the Evacuation Station Hoses.
5. Close the vacuum pump valve and turn the pump off. Monitor the
system pressure for 15 minutes.
6. If the system pressure remains below 2000 microns for 5 minutes, start
the vacuum pump, open the vacuum pump valve and pump the system
down to 500 microns. Close the vacuum pump valve and turn the pump
off. Proceed to Step 9.
7. If pressure rise above 2000 microns in 5 minutes, additional pumping
may be required or a leak may exist. A rapid rise in system pressure
may indicate the presence of a leak. A slow rise in a system pressure
may indicate a need for additional pumping time due to moisture in a
system. Check for leaks as required. Repeat Steps 5 and 6 until the
system pressure remains below 2000 microns for 5 minutes. Proceed to
Step 9.
8. Remove the valve magnets from the normally closed Liquid Injection
Solenoid, Liquid Line Solenoid Valves and Defrost Solenoid and
reinstall the valve coil and retaining nut on the valve stems.
9. The system is ready to be charged with refrigerant.
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