16
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 great-
er than 5000 ohms.
3. Check for proper wiring of resistor assembly.
4. Make sure heater size installed is an approved size for out-
door 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.
Table 5 – FE4 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
STATUS CODE 36, HEATER OUTPUT NOT SENSED
WHEN 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 energizes either heater stage and does not detect
the 24--Vac 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 prop-
erly).
4. Check motor windings section following instructions in
Section C. ECM Motor Troubleshooting.
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 section E,
Emergency Heating and Cooling Modes). No further fan coil
troubleshooting information will be available at the User Interface
until communications are reestablished.
Check system wiring to be sure the User Interface is powered and
connections are made A to A, B to B, etc. and wiring is not
shorted. Mis--wiring or shorting of the ABCD communications
wiring will not allow successful communications. Correcting
wiring faults will clear the code and reestablish communications.
Shorting or mis--wiring the low voltage system wiring will not
cause damage to fan coil control or to User Interface but may cause
the low voltage fuse to open.
STATUS CODE 46, BROWNOUT CONDITION:
If the secondary voltage of the transformer falls below 15Vac for a
period exceeding four seconds, Status Code 46 will be displayed
on STATUS LED.
If system includes a non--communicating outdoor air conditioner
or heat pump, the User Interface will command the fan coil to turn
off Y output controlling compressor.
When secondary voltage rises above 17Vac for more than four
seconds, the brownout condition is cleared and normal system
operation will resume subject to any minimum compressor off
delay function which may be in effect. Brownout does not affect
blower or electric heater operation.
STATUS CODE 53, OUTDOOR AIR TEMPERATURE
SENSOR FAULT:
If an OAT sensor is found at power--up, input is constantly checked
to be within a valid temperature range. If sensor is found to be
open or shorted at any time after initial validation, Status Code 53
will be displayed at amber STATUS LED.
Check for faults in wiring connecting sensor to OAT terminals.
Using an Ohmmeter, check resistance of thermistor for a short or
open condition.
If thermistor is shorted or open, replace it to return the system to
normal operation. If fault is in the wiring connections, correcting
the fault will clear the code and return the system to normal
operation.
NOTE: If fault condition is an open thermistor or a wiring
problem that appears to be an open thermistor and the power to the
fan coil control is cycled off, the fault code will be cleared on the
next power--up but the fault will remain and system operation will
not be as expected. This is because on power--up, the fan coil
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