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PRE-START-UP
System Checkout
When the installation is complete, follow the system checkout
procedure outlined below before starting up the system. Be sure:
1.
Voltage is within the utilization range specifications of the
unit compressor and fan motor, and voltage is balanced for
3-phase units.
2.
Fuses, breakers and wire are correct size.
3.
Low voltage wiring is complete.
4.
Piping and system flushing is complete.
5.
Air is purged from closed loop system.
6.
System is balanced as required. Monitor if necessary.
7.
Isolation valves are open.
8.
Water control valves or loop pumps are wired.
9.
Transformer switched to lower voltage tap if necessary.
10. Service/access panels are in place.
11. Control field-selected settings are correct.
Wire Control Connections
All units have the option for a control package for use with a field
installed thermostat or DDC (Complete C or Deluxe D) or a
factory installed DDC controller capable of standalone operation
(W2W Open).
IMPORTANT: Jumpers and DIP switches should only be
clipped when power to control board has been turned off.
COMPLETE C AND DELUXE D CONTROL
All control wiring is connected to a terminal block located in the
unit electrical box. Refer to the unit wiring diagram for connection
details.
WARNING
To avoid possible injury or death due to electrical shock, open
the power supply disconnect switch and secure it in an open
position during installation.
WARNING
Do not route control wiring through the same conduit as power
supply wiring. Electrical noise and transients from the power
wiring can cause communication issues or damage to the
control wiring and connected control components.
Units with the Complete C or Deluxe D control packages are
controlled using the included thermostat inputs (R, O, Y1, Y2, C)
along with a two-stage thermostat or field installed Direct Digital
Controller (DDC). NOTE: The reversing valve on the unit is
energized when the unit is in the cooling mode.
AUXILIARY RELAY (DELUXE D ONLY)
All units with Deluxe D control include an auxiliary relay that can
be field wired to enable a field provided loop pump or solenoid
valve when there is a call for compressor operation.
ENERGY MANAGEMENT SWITCH (DELUXE D ONLY)
All units with Deluxe D control include an energy management
switch (EMS) relay that can be field wired to disable unit
operation when a 24v signal is removed from the relay. Removing
the 24v signal causes the relay to open, which cuts 24v power to
the unit control circuit. All unit components will be disabled when
the EMS is deactivated. (See Fig. 11.)
PHASE MONITOR
All 3-Phase units with Deluxe D Control will include a 3-Phase
Line Monitor that protects against phase loss, phase reversal, and
phase unbalance. Ideally suited to protect your unit's scroll
compressor(s) from reverse rotation.
ALARM OUTPUT
If the unit is being connected to a thermostat or DDC control with
an alarm indicator, this connection is made at the unit malfunction
output on the Unit Protection Module (UPM). See malfunction
output section of Configure Unit Control Components.
W2W OPEN CONTROL
W2W Open is a factory installed DDC controller. W2W Open is
not compatible with thermostats or third-party temperature
sensors.
All W2W Open wiring is completed at the W2W Open control
board. See the applicable wiring diagrams within this document
for details. For further instructions on W2W Open, please visit
HVACPartners.com or Carrier.com for the W2W Open
Integration Guide and Points/Properties Guide.
CONTROL TRANSFORMER
All units include a 75VA transformer. The VA capacity of the
transformer should be considered when applying low voltage ac-
cessories, such as shut off valves, thermostats, or DDC controls.
Configure Unit Control Components
Each unit is provided with a unit protection module (UPM) which
controls the compressor and provides the unit safety controls and
monitoring. See Fig. 16-18 for the UPM board layout and Freeze
Sensor.
Safety Controls include the following:
1.
High Pressure Switch (HPS):
located in the refrigerant discharge line and set for a
high-pressure cutout control of 600 PSIG. A single HPS is
wired across HPC on UPM1 and two HPS are wired across
HP1 and HP2 on UPM2.
2.
Low Pressure Switch (LPS):
located in the unit refrigerant suction line and set for a
low-pressure cutout of 40 PSIG. A single LPS is wired across
LPC on UPM1 and two LPS are wired across LP1 and LP2
on UPM2.
Source Side Freeze Protection (FS Source):
3.
mounted close to coaxial coil to monitor refrigerant
temperature between the coaxial refrigerant to water heat
exchanger and the thermal expansion valve and prevent water
freezing conditions. Wired Across Freeze 1 terminals on the
UPM.
4.
Load Side Freeze Protection (FS Load):
mounted close to coaxial coil to monitor refrigerant
temperature between the coaxial refrigerant to water heat
exchanger and the thermal expansion valve to prevent water
freezing conditions. Wired Across Freeze 2 terminals on the
UPM.
The default limit trip for both FREEZE sensors 1 and 2 is 26°F
refrigerant temperature. However, this can be changed to 15°F by
cutting the associated resistor (UPM I: R30 Source, R24 Load;
UPM II: R17 Source, R77 Load). Typically, only the source side
freeze protection would be adjusted to account for systems
utilizing anti-freeze with low entering water temperatures
(<40°F). If the temperature drops below or remains at the freeze
limit trip for 30 seconds, the controller will shut down the
compressor and enter a soft lockout condition.
NOTE: Freeze protection will not guard against the loss of water
flow. A flow switch is recommended to prevent the unit from
running if water flow is lost or insufficient.
21
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