CSR-20 & CSR-40, September 1999
Refrigeration System Diagnosis and Service
Charging the System with Refrigerant
6-15
Charging the System with Refrigerant
Unit Charging by Weight (from an Evacuated
Condition)
1.
Close valve V4.
2.
Open the Gas Ballast valve (located on top of the pump
housing behind the handle).
3.
Stop the vacuum pump.
4.
The discharge valve and receiver outlet valves remain
mid-seated.
5.
Connect the refrigerant tank with gauge manifold to the
evacuation station (see “Evacuation Station and Unit
Hookup” on page 6-12).
6.
Weigh the tank of refrigerant.
7.
Check unit data plate for the required weight of refrigerant
charge. Then subtract the unit charge weight from the
total weight of the refrigerant tank. This provides the
final tank weight after the unit receives a full refrigerant
charge.
8.
Set the refrigerant tank for liquid removal. Open the hand
valve on the tank.
9.
With the unit OFF, open the gauge manifold hand valve
and charge liquid refrigerant into the system.
10. Close the refrigerant tank hand valve when the correct
amount (by weight) of refrigerant has been added or if the
system will take no more liquid.
The unit is now ready to have the Evacuation Station
removed.
Evacuation Station Removal
1.
Close the high pressure hand valve on the gauge manifold.
2.
Close the refrigerant tank hand valve.
3.
Open the hand valve at the gauge manifold and read suc-
tion pressure.
4.
Operate the unit in cool mode until the suction pressure
decreases below 385 kPa, 3.85 bar, 50 psig.
5.
Back seat the suction line access service valve.
6.
Stop the unit.
7.
Remove the hoses from the suction and and discharge line
access service valves.
8.
Seal and solder the suction and discharge line process
tubes to remove piercing type access service valves from
unit (see “Installing and Removing Piercing Type Service
Valves and a Gauge Manifold Set” in this chapter).
9.
Leak check the process tubes with an electronic leak
detector.
10. Start the unit and perform a controller Pretrip Test to veri-
fy correct refrigerant charge and unit operation.
Compressor Replacement
Removal
1.
Remove the compressor compartment bracket.
2.
Recover the refrigerant charge from the unit (see
“Refrigerant Recovery” in this chapter).
3.
Disconnect the unit from the three-phase power supply.
4.
Remove the three-phase electric power connection from
the compressor.
5.
Unsolder the discharge line, suction line and liquid injec-
tion line from the compressor.
6.
Remove the compressor mounting tray bolts and nuts.
7.
Slide the compressor from the unit.
8.
Keep the compressor ports covered to prevent dust, dirt,
etc., from falling into the compressor.
9.
Drain and measure the compressor oil that remains in the
compressor.
NOTE: The compressor oil must be removed
from the compressor and measured so that the
same amount of oil can be added before placing
the new compressor or repaired compressor in
the unit.
Installation
1.
Add new compressor oil to the new compressor. Add an
amount equal to the amount removed from the old com-
pressor.
CAUTION: Use ONLY Polyol Ester based refrig-
eration compressor oil, P/N 203-433. Keep
Polyol Ester based compressor oil in tightly
sealed containers. If Ester based oil becomes
contaminated with moisture or standard oils, dis-
pose of properly — DO NOT USE!
2.
Clean the tubes for soldering.
3.
Slide the compressor into the unit. Install mounting bolts,
washers and nuts, and tighten.
4.
Solder the discharge line, suction line and liquid injection
line to the compressor.
NOTE: Thermo King strongly recommends that
dry nitrogen be used to purge the system during
any solder operations (see “Using Pressurized
Nitrogen” in this chapter).
