Start-Up Procedures - Trane RTAA-70 Installation & Maintenance Manual

108

Start-Up Procedures

If the pre-start checkout, as discussed above, has been completed, the unit is
ready to start. The Clear Language Display is shown in
Language Display Sequence of Operation is shown in
each step, in sequence, as follows:
• Press the Stop key on the Clear Language Display.
• As necessary, adjust the setpoint values in the Clear Language Display
menus, as describe in "Clear Language Display Key Pad Overview" .
• Close the fused-disconnect switch for the chilled water pump. Energize
the pump to start chilled water circulation.
• Check the service valves on the discharge line, suction line, oil line and
liquid line for each circuit. These valves must be open (backseated) before
starting the compressors.
CAUTION
Compressor Damage!
To prevent compressor damage, do not operate the unit until all
refrigerant and oil line service valves are opened.
• Energize the compressor sump heaters, if not already energized. Also
close the unit-mounted disconnect, if used.
CAUTION
Compressor Damage!
The compressor sump heaters must be energized for a minimum
of 24 hours prior to unit operation, to prevent compressor
damage caused by liquid refrigerant in the compressor at
start-up.
• Verify that the evaporator heat tape is energized.
• Verify that the chilled water pump runs for one minute after the chiller is
commanded to stop (for normal chilled water systems). See Interlock
Wiring.
• Press the Auto key. If the chiller control calls for cooling and all safety
interlocks are closed, the unit will start. The compressor(s) will load and
unload in response to the temperature of the leaving chilled water tem-
perature.
If optional low-ambient lockout is used, outside air temperature must be
above the minimum starting ambients, as shown in
operation. Also refer to the wiring diagrams.
Once the system has been operating for approximately 30 minutes and has
become stabilized, complete the start-up procedures, as follows:
• Check the evaporator refrigerant pressure and the condenser refrigerant
pressure under Refrigerant Report on the Clear Language Display. The
pressures are referenced to sea level (14.6960 psia).
• Check the liquid line sight glasses. The refrigerant flow past the sight
glasses should be clear. Bubbles in the refrigerant indicate either low
Figure 35 and Clear
Figure 1. Complete
Table 1, for continued unit
RTAA-SVX01A-EN