Installation and Maintenance Manual

Installation - Mechanical
72 RLC-SVX09H-EN
RTUD Chilled Water Flow Control
Oil Charge Determination
The RTUD unit is factory charged with the amount of oil
required by the system. No additional oil is required for
field installed piping.
Outdoor AirTemperature Sensor
Installation Requirements
The outdoor air temperature sensor is optional for the
RTWD water cooled units, but is a required sensor for the
RTUD compressor chiller units.The sensor is required as
an important input to the condenser fan control algorithm
as well as for the low outdoor air ambient lockout feature.
The temperature sensor probe is shipped separately
inside the control panel.
It is necessary for the chiller installer to locate and install
the separate outdoor air sensor probe at the remote air
cooled condenser at a location to sense the coil’s entering
air temperature, while avoiding direct sunlight. It should
be located at least 2” from the coil face and somewhere
“in-between” the two refrigerant circuits. Where the
condenser installation is such that the two refrigerant
circuit’s condensers are physically separate from each
other, or one circuit is more likely to see re-circulated
warmer air, an attempt should be made to locate the probe
to see an average temperature of the two separate
condensers.
Important: The probe provided must not be substituted
with another probe, as the probe and the
electronics are“matched / calibrated” at the
factory for accuracy.
A twisted pair sheathed cable shall be run and connected
between the probe at the remote condenser and its LLID
module in the chiller control panel.The sensor’s circuit is
a class II power limited analog circuit and therefore the
wire should not be run in close proximity to any power or
line voltage wiring.The splices at the condenser end,
should be made to be water tight.The wire run should be
physically supported at equal intervals with consideration
for safety and reliability/durability with wire ties or similar
to meet local codes.
Fan Control for the Remote Air Cooled
Condenser
The CH530 Controls for the RTUD compressor chiller
provide as an option, the flexible and full control of 2-
circuit remote air cooled condenser fans. In addition to the
option for controlling between 2 to 8 fixed speed fans per
circuit (or multiples thereof), a separate additional option
includes the ability to control either two speed fans or
variable speed fan/drive combinations in conjunction with
other fixed speed fans, to provide low ambient outdoor air
temperature capability.The controls will also provide an
option for a simple per circuit interlock output (in lieu of
actual fan control) to use in the scenario in which
independent fan head pressure or differential pressure
controls (by others) is applied. See "Fan Control By Others"
on Page 164 for more information. It is recommended
however, that for the best overall unit performance, the
integral fan control option is selected.
The controls support control of a remote, air cooled
condenser fan deck, from 2 to 8 fans per circuit (1-8 fans for
variable speed). It supports options to control the
following types of standard ambient outdoor air
temperature fan decks: 1) all fans fixed speed, and 2) all
fans two speed. It will also support the following low
ambient outdoor air temperature fan decks 1) one fan per
circuit isTwo-Speed, (remaining fans fixed speed), and 2)
One fan per circuit is variable speed i.e. variable frequency
drive (VFD), (remaining fans fixed speed). In the variable
fan low ambient outdoor air option the VFD fan and fixed
speed fans are sequenced accordingly to provide
continuous control from 0-100% air flow per circuit. Fan
staging provides the correct combination of fixed speed
fan relay, VFD relay (to enable operation of the VFD), and
speed outputs to provide air flow control commanded by
the fan algorithm running inside the CH530 Main
Processor. The fan deck arrangement is independently
configurable per circuit.
Since the condenser is provided separately from the RTUD
compressor chiller, the RTUD electrical panel design does
not provide for condensing unit’s control power
requirements. The chiller’s control power transformer is
not sized to provide the control power for the additional
fan contactor loads. The CH530 controls, when properly
optioned, will provide for pilot duty rated relays, low
voltage binary inputs, and low voltage analog outputs to
control the remote contactors and inverters provided by
others.The CH530 fan control relays located in the chiller
control panel, are intended to control the fan contactors
that are located in the remote air cooled condenser panel.
The Fan Control Relays are rated for up to 7.2 Amps
resistive, 2.88 Amps pilot duty 1/3 HP, 7.2 FLA at 120 VAC,
and up to 5 Amps general purpose at 240 VAC. All wiring
NOTICE:
Equipment Damage!
Add initial field refrigerant charge only through the
service valve on the liquid line, not the service valves on
the evaporator, and insure that water is flowing through
the evaporator during the charging process. Failure to
do the above could result in equipment damage.
NOTICE:
Equipment Damage!
ALL RTUD unit chilled water pumps MUST be
controlled by the Trane CH530 to avoid catastrophic
damage to the evaporator due to freezing