Trane RTHD

RTHD-SVX01D-EN 121
Unit Start-up
Limit Conditions
CH530 will automatically limit certain operating parameters during startup
and run modes to maintain optimum chiller performance and prevent nui-
sance diagnostic trips. These limit conditions are noted in Table 25.
Seasonal Unit Start-Up Procedure
1. Close all valves and re-install the drain plugs in the evaporator and con-
denser heads.
2. Service the auxiliary equipment according to the start-up/maintenance
instructions provided by the respective equipment manufacturers.
3. Vent and fill the cooling tower, if used, as well as the condenser and pip-
ing. At this point, all air must be removed from the system (including each
pass). Close the vents in the evaporator chilled water circuits.
4. Open all the valves in the evaporator chilled water circuits.
5. If the evaporator was previously drained, vent and fill the evaporator and
chilled water circuit. When all air is removed from the system (including
each pass), install the vent plugs in the evaporator water boxes.
CAUTION
Equipment Damage!
Ensure that the oil sump heaters have been operating for a
minimum of 24 hours before starting. Failure to do so may result
in equipment damage.
6. Check the adjustment and operation of each safety and operating control.
7. Close all disconnect switches.
8. Refer to the sequence for daily unit startup for the remainder of the sea-
sonal startup.
Table 25 Limit Conditions
Running - Limited
The chiller, circuit, and compressor are currently running, but the operation of the
chiller/compressor is being actively limited by the controls. Further information is
provided by the sub-mode.
Capacity Limited by High
Cond Press
The circuit is experiencing condenser pressures at or near the condenser limit setting. The
compressor will be unloaded to prevent exceeding the limits.
Capacity Limited by Low
Evap Rfgt Temp
The circuit is experiencing saturated evaporator temperatures at or near the Low Refrigerant
Temperature Cutout setting. The compressors will be unloaded to prevent tripping.
Capacity Limited by Low
Liquid Level
The circuit is experiencing low refrigerant liquid levels and the EXV is at or near full open. The
compressor will be unloaded to prevent tripping.
Capacity Limited by High
Current
The compressor is running and its capacity is being limited by high currents. The current limit
setting is 120% RLA (to avoid overcurrent trips).
Capacity Limited by Phase
Unbalance
The compressor is running and its capacity is being limited by excessive phase current
unbalance.