5
grounding
Warning:
the unit cabinet must have an uninterrupted or
unbroken electrical ground to minimize personal
injury if an electrical fault should occur. do not
use gas piping as an electrical ground!
This unit must be electrically grounded in accordance with
local codes or, in the absence of local codes, with the National
Electrical Code (ANSI/NFPA 70) or the CSA C22.1 Electrical
Code. Use the grounding lug provided in the control box for
grounding the unit.
coreSense
tm
diagnostics module
(Select models only)
The CoreSense
TM
Diagnostics Module (
Figure 2
) is a
breakthrough innovation for troubleshooting heat pump and
air conditioning system failures. The module installs easily
in the electrical box of the outdoor unit near the compressor
contactor.By using the compressor as a sensor, CoreSense
Diagnostics helps the service technician more accurately
troubleshoot system and compressor fault conditions.
A flashing LED indicator communicates the ALERT code
and a diagnostic key is also imprinted on the side of the
module to quickly direct the technician to the root cause of
a problem.
Alert identification codes are also listed in
Table
10, (page 12)
.
Compressor Protection
The CoreSense
TM
Diagnostics module utilizes proprietary
algorithms to protect the compressor and system from
repeated trips of system pressure controls and the compressor
internal overload. The protection terminal of the module should
be wired in series with the system low pressure and high
pressure cutouts, as well as the compressor contactor. When
the module detects a series of trips as described below, it
will activate a lockout feature that opens the normally closed
protection contacts in the module, thereby cutting power to
the contactor and shutting off the compressor.
Resetting Alert Codes
When the CoreSense
TM
Diagnostics module has detected a
series of adverse conditions that have caused it to lockout
the compressor, and after the issue has been resolved, it
is necessary to manually reset the module in order to clear
the present alert code.
The primary way of clearing the code and resetting the alert
is to press the reset button located on the module.
note:
Pressing the reset will require a pin or a mini electronics
screwdriver. This button must be pressed and held for a
minimum of one second for the module to be reset. Pressing
the reset button clears the immediate lock code and the seven
day operating history. It will not clear the permanent module
history. In the case of the three-wire module, the codes can
be reset or cleared by cycling power to the module. This can
be done by disengaging the Common (C) terminal. This will
not clear the seven day operating history.
Figure 2. coreSense
tm
diagnostics module
Compressor
Common Wire
Reset Button
Trip / Lock
(Red LED)
Run / Alert
(Yellow LED)
thermostat connections
• Thermostat connections should be made in accordance
with the instructions supplied with the thermostat and the
indoor equipment.
• The outdoor unit is designed to operate from a 24 VAC
Class II control circuit. The control circuit wiring must comply
with the current provisions of the NEC (ANSI/NFPA 70)
and with applicable local codes having jurisdiction.
• The low voltage wires must be properly connected to
the units low voltage terminal block. Recommended wire
gauge and wire lengths for typical thermostat connections
are listed in
Table 2
.
• The thermostat should be mounted about 5 feet above the
floor on an inside wall. DO NOT install the thermostat on
an outside wall or any other location where its operation
may be adversely affected by radiant heat from fireplaces,
sunlight, or lighting fixtures, and convective heat from
warm air registers or electrical appliances. Refer to the
thermostat manufacturer’s instruction sheet for detailed
mounting and installation information.
Start Up & adJUStmentS
pre-Start check list
√
Verify the indoor unit is level and allows proper condensate
drainage.
√
Verify the outdoor coil and top of the unit are free from
obstructions and debris, and all equipment access/control
panels are in place.
√
Verify air filters are cleaned and properly installed.
√
Verify duct work is sealed to prevent air leakage.
√
Verify line voltage power leads are securely connected
and the unit is properly grounded.
√
Verify low voltage wires are securely connected to the
correct leads on the low voltage terminal strip.
√
Verify power supply branch circuit overcurrent protection
is sized properly.
√
Verify the thermostat is wired correctly.
table 2. thermostat Wire gauge
thermoStat
Wire gaUge
maximUm recommended
thermoStat Wire length (Ft)
24
25
22
45
20
70
18
110
