FCM/A5, FEV, FJM, FEM4, FHMA5, FMA4/5, FM(C,U)5, FS(A,M,U)4, FTMA5, F(V,X)M4, F5M4, REM4, WA(H,M,P,X) WB(G,H)L, WC(G,H)L: Service and Maintenance
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
15
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 12VDC 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 (ECM Motor Troubleshooting on p13).
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 SELECTION:
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 replacement 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 replaced
with proper size motor. Fan coil control will not respond 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 displayed 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 instructions
in (ECM Motor Troubleshooting on p13).
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 combination of indoor and
outdoor components installed. Fan coil control will read IDR value
connected to Pins 5 and 8 of heater harness connector. If no resistor is
found, system User Interface will prompt installer to verify that no
heater is installed.
Verifying that this is correct will establish that fan coil 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 fan coil and outdoor 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 5 and 8 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
heater header and check for a resistance value greater than 5000
ohms.
3. Check for proper wiring of resistor assembly.
4. Make sure heater size installed is an approved size for outdoor unit
and fan coil sizes installed.
NOTE: Fan coil control will not operate electric heater until this Status
Code is resolved. If the heater size is set through the User Interface, the
heater will be operated as a single stage heater. If staging is desired, the
IDR value must be read in by the fan coil control.
STATUS CODE 36, HEATER OUTPUT NOT SENSED WHEN
ENERGIZED:
Fan coil control is provided with circuitry to detect presence of a 24VAC
signal on Electric Heater stage 1 and stage 2 outputs.
If fan coil control energizes either heater stage and does not detect the
24VAC signal on output, Status Code 36 will be displayed on the
STATUS LED Fan coil control will continue to energize heater output(s)
and adjust blower operation to a safe airflow level for energized electric
heat stage(s).
To find the fault, check for 24VAC on heater stage outputs. Fan coil
control or sensing circuit may be bad.
NOTE: It may be useful as an electric heater troubleshooting procedure
to disconnect the system communications to force Status Code 16
enabling of emergency heat mode. It is difficult to know which heater
output is energized or not energized in normal operation. When fan coil
is operated in emergency heat mode using electric heaters, both outputs
are energized and de-energized together. Terminal strip inputs to control
can then be connected R to W to turn on both electric heat outputs.
Heater output sensing circuits can then be checked to resolve Status
Code 36 or 37 problems.
STATUS CODE 41, BLOWER MOTOR FAULT:
If MOTOR LED is lit and flashing and motor does not run:
1. Check STATUS LED. If STATUS LED is indicating Status Code
41, motor control has detected that the motor will not come up to
speed within 30 seconds of being commanded to run or that the
motor has been slowed to below 250 rpm for more than 10 seconds
after coming up to speed. Motor wiring harness and fan coil control
are operating properly, do not replace.
2. Check to be sure that the blower wheel is not rubbing the housing.
3. Check motor to be sure that the motor shaft is not seized (motor
control module must be removed and electronics disconnected from
windings to perform this check properly).
4. Check motor windings section following instructions in (ECM
Motor Troubleshooting on p13).
If all these checks are normal, the motor control module may need
replacement.
STATUS CODE 16, SYSTEM COMMUNICATION FAULT:
If, at any time, system communications are not successful for a period
exceeding two minutes, the fan coil control will only allow emergency
heating or cooling operation using a common thermostat, a
non-communicating outdoor unit, and the R, C, Y, O,W outdoor unit
terminal strip connections and will display Status Code 16 on the amber
STATUS LED. See (Emergency Heating and Cooling Modes on p16).
Table 8 – FCM Self-identifying Resistor Values
Heater Size kW Resistor Ohms Nominal
No heater Open
9 11k
15 18k
20 24k
24 33k
30 39k
Hydronic Heat 270k
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