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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 exists.
2. Recheck airflow and system static pressure using UI service
screens with access panel in place.
NOTE: Blower motor faults ,,vill not cause a lockout of blower
operation. The fan coil control will attempt to run the blower motor
as long as UI maintains a demand for airflow. The control ,,vill not
operate electric heaters while a fault condition exists. The control
communicates with the motor at least once every five seconds, even
when the motor is idle. If, during operation, the 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 Fan Coil Control
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
unit 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
(;ode
in Section
E, Fan (;oil
Control
Troubleshooting.
E. Fan
('oil Control
Troubleshooting
Fan coil control
faults
indicated
by flashing
codes on the amber
system
STATUS
LED
can be
resolved
using
troubleshooting
information
provided
below.
(;odes
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
(;ode
to be flashed.
All
existing
faults, as well as a fault history, can be viewed
at UI.
STATUS
(;ODE
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
(;ODE
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 i 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
(;ode
37 will be
displayed
on STATUS
LED.
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 UI and check
heater
stage
24-vac
outputs.
2. Disconnect
electric heater at power
and check heater wiring
for faults. See Status Code 36 for more information.
STATUS
(;ODE
44, MOTOR
COMMUNICATION
FAULT
When motor is commanded
to operate,
the MOTOR
LED will be
turned on and will flash each time instructions
are sent to the motor.
15
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
comnmnicating
with the motor, even
when
the motor
and MOTOR
LED
are off. If motor
does not
acknowledge
receipt
of communications,
the fan coil 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 i (+) 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, Indoor Fan Motor
Troubleshooting.
If the MOTOR
LED is off, STATUS
LED is indicating
a Status
Code 44 and motor is running:
1. Disconnect
the motor harness at tlm 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
SELECTION
On initial start-up,
the fan coil control
shall poll motor for its size
data and check unit size data stored in the control memory.
1. If motor size is incorrect
for unit size or 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
replacement
fan coil
control board
is installed),
system UI
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
replaced
with proper
size motor.
Fan coil control
will not
respond
to operation
requests
until this fault condition
is
resolved.
STATUS
CODE
26, INVALID
HEATER
SIZE
On initial power-up,
fan coil control will write into memory
electric
heater size as read from heater if heater is provided
with Identifier
Resistor
(IDR). Heater size must be valid for the installed unit. Fan
coil control will read IDR value connected
to pins 1 and 2 of heater
harness
connector.
If no resistor
is found,
system
UI will prompt
installer
to verify
that no heater is installed.
Verifying
that this is
correct will establish
that
the unit is operating
without
an electric
heater accessory.
Upon choosing
negative
option,
installer
will be
prompted
to select heater size installed
from a list of valid heater
sizes for unit size installed.
If heater
ID resistor
value read is invalid,
Status
Code 26 will be
displayed
on STATUS
LED.
If heater installed is equipped
with a resistor connected
to pins 1 and
2 of heater
harness
connector
and status code 26 is displayed
on
STATUS
LED:
1. Check wiring harness connections
to be sure connections
are
secure.
2. If symptoms
persist,
disconnect
wiring
harness
at fan coil
control board
and check for a resistance
value greater than
5000 ohms.
3. Check for proper
wiring of resistor
assembly.
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