Thermo King T-1080S, Руководство по обслуживанию

Страница: 126 / 191

Refrigeration Service Procedures
125
Figure 216: Pressure Rise Graphs
Unit Charging
NOTE: Before charging, make sure that the
refrigerant lines from the gauge manifold to the
refrigerant supply bottle have been evacuated or
purged.
1. Backseat the suction service valve and make
sure the receiver tank outlet valve is still open.
2. Set the refrigerant supply bottle for liquid and
open the gauge manifold hand valve. Add
liquid refrigerant until the system has the
recommended refrigerant charge (see unit
serial number nameplate or the
“Specifications” chapter), or until the system
will take no more liquid. The remainder of the
charge will be added as a liquid through the
suction service valve if more refrigerant is
required.
3. After the liquid refrigerant is added, close the
gauge manifold hand valve.
4. Back seat (close) the receiver tank outlet
valve, remove the evacuation station hoses,
and install the cap on the service port for the
receiver tank outlet valve.
5. If the unit is not fully charged, attach the
gauge manifold set to the suction service valve
and the discharge service port, and open the
suction service valve one turn. A low loss
fitting must be used on the hose connected to
the discharge service port.
6. Open the refrigerant supply valve for liquid.
7. Start the unit and use the Service Test mode to
run the unit in high speed cool. See the
appropriate Microprocessor Diagnostic
Manual for information about the Service Test
mode.
8. Observe the suction pressure and slowly open
the gauge manifold hand valve to allow liquid
refrigerant to flow into the suction service
Leak
Isolate the pump from the system by closing the
proper valve. Watch the movement of the vacuum
gauge needle. If the needle continues to rise,
this is an indication that a leak exists in the unit
or the connecting line. The leak must then be
located and eliminated.
Moisture
Should the needle show a pressure rise but
finally level off to practically a constant mark,
this is an indication that the system is vacuum
tight but is still too wet, requiring additional
dehydration and pumping time.