11
Wrong Easy Select Board selection. Selecting an outdoor unit or
electric heater smaller than actually installed will result in low
airflow for the application.
G not energized with call for cooling or heating. This triggers
Super Comfort Heat or SuperDehumidify mode which delivers 50
percent of cooling airflow.
J1 jumper pulled with no thermidistat or dehumidistat installed.
The J1 jumper ties the DH terminal to R and is installed at the
factory. When pulled, a Thermidistat or dehumidistat supplies a
24--V signal to DH when there is no call for dehumidification
(reverse logic). When there is no signal on DH, the motor reduces
airflow to 80 percent for better dehumidification.
Airflow Too High:
Wrong Easy Select Board selection. Fan coil is factory set for the
largest outdoor unit and largest electric heater. Select sizes that are
actually installed.
Continuous fan set too high for two--speed applications. Set to
MED or LO.
Motor Will Not Stop:
Allow time for off delay to time out. In units built before serial
number 0101A, any W call will have a two--minute off delay
independent of delay selection. This is programmed into the motor
and cannot be overridden.
In units built after 0101A, the off delay on any W call is one
minute and cannot be overridden.
Some power--stealing thermostats could bleed enough voltage to
cause motor to run slowly when there is no heating or cooling call.
Disconnect thermostat wires and wait two minutes to see if motor
stops. If it stops, replace thermostat, or install resistor per
thermostat installation instructions.
Motor Will Not Start:
See following section, “Troubleshooting ECM2.3/5.0 Motor and
Controls
C. Troubleshooting ECM2.3/5.0 Motor and Controls
ELECTRICAL OPERATIONS HAZARD
Failure to follow this caution may result in equipment
damage or improper operation.
High voltage is always present at motor. Disconnect power to
unit before removing or replacing connectors or servicing
motor. Wait at least five minutes after disconnecting power
before opening motor.
CAUTION
!
The ECM/ICM motor used with this product contains two parts:
the control module and the motor winding section. Do not assume
the motor or module is defective if it will not start. Go through the
steps described below before replacing control module, Easy Select
Board or entire motor. The control module is available as a
replacement part.
D. If Motor Turns Slowly:
1. It is normal operation to run noticeably slower if G terminal
is not energized in cooling or heat pump heating modes.
2. Attach blower access panel. Motor may appear to run
slowly if access panel is removed.
E. If Motor Does Not Run:
Turn power off, wait five minutes and check the following:
1. With power turned off, check 5--amp fuse on Easy Select
Board.
2. Check all plugs and receptacles for any deformation or cor-
rosion that could cause bad connections. Be sure plugs are
fully seated.
ELECTRICAL OPERATION HAZARD
Failure to follow this caution may result in equipment damage
or improper operation.
DO NOT remove or apply 5--pin plug on motor with power
on. Arcing could occur, which can damage control module
CAUTION
!
Turn power back on and check the following:
3. Check for 24Vac on SEC1 and SEC2. If no voltage is
present, check transformer.
4. Verify that approximately 230Vac is present at motor.
5. Verify low voltage control signals to motor according to
procedure below.
Use following procedure to check low voltage signals:
The ECM motor in these fan coils receive low voltage signals from
the Easy Select Board through the wiring harness assembly. The
combination of pins energized at the motor determines the speed
the motor will run. The procedure below isolates the fan coil from
all external devices such as a thermostat, condensing unit,
humidifier or electronic air cleaner. There is also a specific
troubleshooting example to demonstrate the process. Table 7
provides information needed to verify that the correct voltages are
present at the motor and the Easy Select Board.
THERMOSTAT:
1. Remove all thermostat and accessory wires from Easy Se-
lect Board.
2. On Easy Select Board, jumper screw terminals (1 at a time):
R -- G , R -- Y / Y 2 , R -- Y 1 , R -- W 1 , R -- W 2 . I f m o t o r r u n s i n a l l
cases, check thermostat outputs. Thermostat wires may be
broken, or thermostat may be miswired, configured incor-
rectly, or defective. If the motor does not run, or runs in
some cases, but not others, continue this procedure to check
wiring harness and circuit board.
WIRING HARNESS:
1. Remove 16--pin plug from motor.
2. Check for appropriate voltages on 16--pin connector with
screw terminals jumpered. (See Table 2.)
3. If signals check correctly, and motor does not run, inspect
wiring harness for loose pins or damaged plastic that could
cause poor connections.
4. If connections are good, either control module or motor is
defective.
5. If proper signals are not present, check circuit board using
procedure below:
12--PIN PLUG (PL--1) ON EASY SELECT BOARD:
1. Completely disconnect wire harness from Easy Select
Board.
2. Jumper the screw terminals one at a time; R--G, R--Y/Y2,
R--Y1, R--W1, R--W2 and check for appropriate voltages on
the Easy Select Board pins. If proper signals are not present,
replace Easy Select Board. If proper signals are present at
the pins and not at 16--pin connector to the motor, the wir-
ing harness is defective.
TROUBLESHOOTING EXAMPLE:
Motor is not running on a call for heat pump heating after
jumpering the Easy Select Board screw terminals as described in
Thermostat section above.
With all thermostat wires removed from Easy Select Board, place a
jumper wire between R and Y/Y2 low--voltage screw terminals on
the Easy Select Board.
1. Check Table 4 for pin number on 16--pin connector associ-
ated with the Y/Y2 signal. The correct pin is No. 14. The far
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