Unit Start Up Procedures - Trane RTAF SE Series Installation Operation & Maintenance

Unit Start Up Procedures

Daily Unit Start Up
The timeline for the sequence of operation begins with a
power-up of the main power to the chiller. The sequence
assumes 2 circuits, 2 compressors, Sintesis air cooled
RTAF chiller with no diagnostics or malfunctioning
components. External events such as the operator placing
the chiller in AUTO or STOP , chilled water fl ow through
the evaporator, and application of load to the chilled-
water loop causing loop water-temperature increases,
are depicted and the chiller responses to those events
are shown, with appropriate delays noted. The effects
of diagnostics, and other external interlocks other than
evaporator water-fl ow proving, are not considered.
Note: unless the UC800 TD7 and building automation
system are controlling the chilled-water pump, the
manual unit start sequence is as follows. Operator actions
are noted.
General
If the present checkout, as discussed above, has been
completed, the unit is ready to start.
1. Press the STOP key on the TD7.
2. As necessary, adjust the set point values on the
TD7 menus using Tracer TU.
3. Close the fused-disconnect switch for the chilled-
water pump. Energize the pump(s) to start water
circulation
4. Check the service valves on the discharge line,
suction line, oil line, and liquid line for each circuit.
These valves must be open (back seated) before
starting the compressors.
5. Verify that chilled-water pump runs for at least one
minute after the chiller is commanded to stop (for
normal chilled-water systems).
6. 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 leaving chilled – water temperature;
After the system has been operating for approximately
30 minutes and has become stabilized, complete the
remaining start up procedures, as follows:
1. Check the evaporator refrigerant pressure and the
condenser refrigerant pressure under Refrigerant
Report on the TD7.
2. Check the EXV sight glasses after enough time has
elapsed to stabilize the chiller. The refrigerant fl ow
through the sight glasses should be clear. Bubbles in
the refrigerant indicate either low refrigerant charge
or excessive pressure drop in the liquid line, or an
expansion valve that is stuck open. A restriction in
the line can sometimes be identifi ed by a noticeable
temperature differential between the two sides of the
restriction. Frost will often form on the line at this
point. Proper refrigerant charges are shown in the
General Information Section;
3. Measure the system discharge superheat.
48
4. Clean the air fi lter located on the door of the control
panel of AFD only on following unit type:
- RTAF HSE sizes 155 and 175 on circuit 1
- RTAF HSE sizes 190 and 205 on each circuit
Seasonal Unit Startup Procedure
1. Close all valves and reinstall the drain plugs in the
evaporator.
2. Service the auxiliary equipment according to the
startup and maintenance instructions provided by the
respective equipment manufacturers.
3. Close the vents in the evaporator chilled-water
circuits.
4. Open all the valves in the evaporator chilled-water
circuits.
5. Open all refrigerant valves.
6. If the evaporator was previously drained, vent and fi ll
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.
7. Check the adjustment and operation of each safety
and operating control.
8. Close all disconnect switches.
9. Refer to the sequence for daily unit start up for the
remainder of the seasonal start up.
CAUTION! Ensure that the compressor and oil separator
heaters have been operating for a minimum of 24 hours
before starting. Failure to do so may result in equipment
damage.
System Restart after Extended
Shutdown
1. Verify that the liquid-line service valves, oil line,
compressor discharge service valves, and optional
suction service valves are open (back seated)
2. Check the oil separator oil level (see Maintenance
procedures section)
3. Fill the evaporator water circuit. Vent the system
while it is being fi lled. Open the vent on the top of
the evaporator while fi lling, and close it when fi lling
is completed.
4. Close the fused-disconnect switches that provide
power to the chilled-water pump.
5. Start the evaporator water pump and, while water is
circulating, inspect all piping for leakage. Make any
necessary repairs before starting the unit.
6. While the water is circulating, adjust the water fl ows
and check the water pressure drops through the
evaporator. Refer to "water-system fl ow rates" and
"water-system pressure drop"
7. Adjust the fl ow switch on the evaporator piping for
proper operation
8. Stop the water pump. The unit is now ready for
startup as described "Startup procedures"
RLC-SVX19A-E4