Trane Rtaaiom3 Manual

121RTAA-IOM-3
Pre-Start
Checkout
General
When installation is complete, but prior
to putting the unit into service, the
following pre-start procedures must be
reviewed and verified correct:
[  ] Inspect all wiring connections to be
sure they are clean and tight.
WARNING: Disconnect all electric
power including remote
disconnects before servicing’
Failure to disconnect power
before servicing can cause severe
personal injury or death.
Caution: Check the tightness of all
connections in the compressor
power...

122RTAA-IOM-3
[  ] Energize the evaporator and
Domestic Water Heater heat tape.
[  ] Fill the evaporator chilled water
circuit. Refer to Table 1 for
evaporator liquid capacities. Vent
the system while it is being filled.
Open the vent on the top of the
evaporator during filling and close
when filling is completed.
Customer Note
The use of improperly treated or
untreated water in this equipment may
result in scaling, erosion, corrosion,
algae or slime. The services of a
qualified water treatment...

123RTAA-IOM-3
Unit Voltage Phasing
It is important that proper rotation of
the compressors be established before
the unit is started. Proper motor
rotation requires confirmation of the
electrical phase sequence of the power
supply. The motor is internally
connected for clockwise rotation with
the incoming power supply phased
A, B, C.
Basically, voltages generated in each
phase of a polyphase alternator or
circuit are called phase voltages. In a
three-phase circuit, three sine wave
voltages are generated,...

124RTAA-IOM-3
1. Turn the Chiller Switch on the UCM
to the STOP/RESET position.
2. Open the electrical disconnect or
circuit protection switch that
provides line power to the line power
terminal block(s) in the starter panel
(or to the unit-mounted disconnect).
3. Connect the phase sequence
indicator leads to the line power
terminal block, as follows:
Phase Seq. LeadTerminal
Black (Phase A).................. L1
Red (Phase B).................... L2
Yellow (Phase C)................ L3
4. Turn power on by...

125RTAA-IOM-3
Start-Up
Procedures
General
If the pre-start checkout, as discussed
above, has been completed, the unit is
ready to start. UCM controls are shown
in Figure 51 and UCM Sequence of
Operation is shown in Figures 56
and 57. Complete each step, in
sequence, as follows:
[  ] Move the Chiller Switch on the UCM
to the STOP/RESET position.
[  ] As necessary, adjust the setpoint
values in the UCM menus, as
described in “Menu Function
Descriptions and Selections”.
[  ] Close the fused-disconnect...

126
RTAA-IOM-3
Figure 56 
Unit Sequence of Operation – RTAA 240 to 400 Tons
(Continued on Next Page) 

127RTAA-IOM-3
(Continued from Previous Page)
2307-1566C 

128
RTAA-IOM-3
Figure 57 
Unit Sequence of Operation – RTAA 130 to 200 Tons
2306-9122A 

129RTAA-IOM-3
Unit Shutdown
Procedures
Temporary Shutdown
and Restart
To shut the unit down for a short time,
use the following procedure:
1. Move the Chiller Switch to STOP/
RESET. The compressors will
continue to operate and, after
unloading for 20 seconds, will stop
when the compressor contactors de-
energize. The condenser fans will be
de-energized at this time.
2. The unit disconnect switch and unit
mounted disconnect (if installed)
should remain closed to keep the
compressor sump heaters...

130RTAA-IOM-3
System Restart After
Extended Shutdown.
Follow the procedures below to restart
the unit after extended shutdown:
1. Verify that the liquid line service
valves, oil line, compressor
discharge service valves and suction
service valves (if installed) are open
(backseated).
Caution: To prevent damage to the
compressor, be sure that all
refrigerant valves are open before
starting the unit.
2. Close the main disconnect and unit
mounted disconnect (if installed) to
energize the compressor sump...