Startup; Compressor Startup; Scroll Compressors - Trane RRU120 D B Series Installation, Operation And Maintenance Manual

Startup

Compressor Startup

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WARNING
Hazardous Service Procedures!
Failure to follow all precautions in this manual and on
the tags, stickers, and labels could result in death or
serious injury.
Technicians, in order to protect themselves from
potential electrical, mechanical, and chemical hazards,
MUST follow precautions in this manual and on the
tags, stickers, and labels, as well as the following
instructions: Unless specified otherwise, disconnect all
electrical power including remote disconnect and
discharge all energy storing devices such as capacitors
before servicing. Follow proper lockout/tagout
procedures to ensure the power can not be
inadvertently energized.When necessary to work with
live electrical components, have a qualified licensed
electrician or other individual who has been trained in
handling live electrical components perform these
tasks.
NOTICE
Compressor Failure!
Unit must be powered and crankcase heaters energized
at least 8 hours BEFORE compressors are started.
Failure to follow these instructions could cause
premature compressor failure.
1. Before initial start up, or if main power has been off for
an extended period of time, compressor crankcase
heater(s) must be operated for a minimum of 8 hours
prior to compressor operation. With main power OFF,
remove jumper between RRUTS Terminals 7 and 8
(Run-Command). Turn main power ON to energize
crankcase heater(s). At end of warm up period turn
main power off, install 7–8 jumper or run command
wires, turn main power on, and resume normal
operation.
2. Attach a set of service gauges onto the suction and
discharge gauge ports for each circuit.
3. Using the Override button located on the Main
Display, select Override and then select Override a
Binary Output. Using the parameters guide in
Table 5, locate compressor overrides. Enable and
check each compressor circuit by selecting
Compressor 1 or Compressor 2 – ON.
34
Table 5. Override (at Home screen)
Override Occupancy
1 of 4 Override Occupancy
Adj. Occupied
Adj. Unoccupied
Adj. OCC-Bypass
Adj. OCC-Standby
Override a Binary Output
(On-Off or Open-Closed)
1 of 4 Binary Outputs
Adj. OA Damper
Adj. Indoor Fan Motor
Adj. Compressor 1
Adj. Compressor 2
Override an Analog Output
1 of 4 Analog Outputs
Adj. Heat Modulation Signal
***NOT USED***
Adj. ERCC Capacity Control
Adj. S/Fan VFD (Optional)
Note: All overrides set must be manually released.
4. To return the unit to normal operation, release all
overrides.
Note: Overrides do not time out. Overrides must be
manually released when startup function is
complete.

Scroll Compressors

5. Once each compressor has started, verify that the
rotation is correct. If a scroll compressor is rotating
backwards, it will not pump and a loud rattling sound
can be observed.
6. If the electrical phasing is correct, before condemning
a compressor, interchange any two leads (at the
compressor Terminal block) to check the internal
phasing. Refer to the following illustration for the
compressor terminal/phase identification. If the
compressor runs backward for an extended period
(15 to 30 minutes), the motor winding can overheat
and cause the motor winding thermostat to open.
2 of 4 Binary Outputs
Adj. Hot Gas Reheat
Adj. Heating
(%)
2 of 4 Analog Output
***NOT USED***
***NOT USED***
RRU-SVX01F-EN