15
MOTOR TURNS SLOWLY:
1. Low static pressure loading of blower while access panel is
removed will cause blower to run slowly. Particularly at low
airflow requests. This is normal, do not assume a fault ex-
ists.
2. Recheck airflow and system static pressure using User Inter-
face service screens with access panel in place.
NOTE: Blower motor faults will not cause a lockout of blower
operation. Fan coil control will attempt to run the blower motor as
long as User Interface maintains a demand for airflow. Fan coil
control will not operate electric heaters while a fault condition
exists. The fan coil control communicates with the motor at least
once every five seconds, even when the motor is idle. If, during
operation, the fan coil control does not communicate with the
motor for more than 25 seconds, the motor will shut itself down
and wait for communications to be reestablished.
D. Using Motor LED in Troubleshooting
The MOTOR LED is connected to the blower motor
communication line and works with the fan coil control
microprocessor and the STATUS LED to provide fan coil
operation and troubleshooting information. When the motor is
commanded to operate, the MOTOR LED will be turned on and
will flash each time instructions are sent to the motor. When the
motor is commanded to stop, the MOTOR LED will be turned off.
If the MOTOR LED is lit, flashing and the motor is running or if
the MOTOR LED is off and the motor is stopped, operation is
normal and no motor fault exists.
If the MOTOR LED is lit, flashing and the motor does not run, or
if the MOTOR LED is off and the motor is running, check the
STATUS LED for the Status Code. Refer to the troubleshooting
instructions for the indicated Status Code in Section E, Fan Coil
Troubleshooting.
E. Fan Coil Troubleshooting
Fan coil faults indicated by flashing codes on the amber system
STATUS LED can be resolved using troubleshooting information
provided below. Codes are listed in order of their priority, highest
to lowest. Though multiple faults can exist at any time, only the
highest priority code will be displayed on STATUS LED. Clearing
the indicated fault when multiple faults exist will cause the next
highest priority Status Code to be flashed. All existing faults, as
well as a fault history, can be viewed at User Interface.
STATUS CODE 45, CONTROL BOARD TEST FAULT:
Fan coil control has failed internal start--up tests and must be
replaced. No other service procedure will correct.
STATUS CODE 37, HEATER OUTPUT SENSED ON
WHEN NOT ENERGIZED:
Fan coil control is provided with circuitry to detect presence of a
24--Vac signal on Electric Heater stage 1 and stage 2 outputs.
If fan coil control detects a 24--Vac signal on either heater stage
output and it is not supplying signal, Status Code 37 will be
displayed on STATUS LED. Fan coil control will turn off output
and command blower motor to supply an airflow determined to be
safe for current operation mode with electric heaters energized.
To find the fault:
1. Stop all system operations at User Interface and check heat-
er stage 24--Vac outputs.
2. Disconnect electric heater at plug/receptacle 2 and check
heater wiring for faults. See Status Code 36 for more in-
formation.
STATUS CODE 44, MOTOR COMMUNICATION FAULT:
The MOTOR LED is connected to the blower motor
communication line and works with the fan coil control
microprocessor and STATUS LED to provide fan coil operation
and troubleshooting information.
When motor is commanded to operate, the MOTOR LED will be
turned on and will flash each time instructions are sent to the
motor.
When the motor is commanded to stop, the MOTOR LED will be
turned off. The MOTOR LED will not flash to indicate
communications when it is turned off.
Fan coil control is constantly communicating with the motor, even
when the motor and MOTOR LED are off. If motor does not
acknowledge receipt of communications, the control will display
Status Code 44 on STATUS LED and continue to try to
communicate with the motor. If motor acknowledges
communication, status code will be cleared.
If MOTOR LED is lit and flashing and motor does not run:
1. Check the STATUS LED. If STATUS LED is indicating a
Status 44 code, check the motor wiring harness for proper
connection to control and motor receptacles.
2. Check motor wiring harness to be sure all wiring complies
with wiring diagram description, makes a complete circuit
from connector to connector and is not shorted.
3. Check 12--Vdc low--voltage supply to motor at Pins 1 (+)
and 2 (--) of motor header connection to fan coil control.
If all checks are normal, fan coil control is good and control
module on motor may need replacement. Check motor and Motor
Control Module following the instructions in Section C. ECM
Motor Troubleshooting.
Shorted or mis--wiring of the low voltage motor harness wiring
will not cause damage to fan coil control or to motor control
module.
If the MOTOR LED is off, STATUS LED is indicating a Status
Code 44 and motor is running:
Disconnect the motor harness at the fan coil control. If motor
continues to run, fan coil control is good and control module on
motor may need replacement
STATUS CODE 25, INVALID MOTOR / MODEL SELEC-
TION:
On initial start--up, fan coil control shall poll motor for its size data
and check fan coil size data stored in fan coil control memory.
1. If motor size is incorrect for fan coil size or fan coil size data
is invalid, Status Code 25 will be displayed on STATUS
LED.
2. If model size data is missing (as is the case when a replace-
ment fan coil control is installed), system User Interface will
prompt installer to enter correct model size from a list of
valid sizes.
3. If motor size is incorrect for model size, motor must be re-
placed with proper size motor. Fan coil control will not re-
spond to operation requests until this fault condition is
resolved.
STATUS CODE 27, INVALID OUTDOOR UNIT SIZE:
On initial power--up, fan coil control will write into memory
outdoor unit size as provided by User Interface in a fully
communicating system.
1. If outdoor unit size is invalid, Status Code 27 will be dis-
played on STATUS LED.
2. User Interface will prompt the installer to choose size from a
list of valid sizes for application with fan coil.
3. Check communications wiring to be sure User Interface has
established communications with outdoor unit or select
proper size from valid size list provided at User Interface.
4. Check motor and motor control module following the in-
structions in Section C. ECM Motor Troubleshooting.
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