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16
Table 9 —
Troubleshooting
Replacement Parts
Quote the unit model number and unit serial number when
ordering replacement parts or contacting the factory about the
unit. This information can be found on the serial plate attached
to the unit. See Fig. 31.
Fig. 31 —Unit Serial Plate (Example)
ERROR
DESCRIPTION
POSSIBLE CAUSES
POSSIBLE SOLUTIONS
dd
Heating / Cooling Mode Conflict
System is in cooling or fan only mode and
heating signal is received from a unit on the
system.
All units should be in cooling mode for system to
stay in cooling mode.
System is in heating mode and cooling
signal is received from a unit in the system.
All units should be in heating mode.
E1
Communication Error Between
Indoor & Outdoor Unit
Signal wires are short-circuited or
disconnected.
Check or reconnect signal wire.
Signal wire close to electromagnetic
source.
Distance signal wires from electromagnetic
source.
PC board fault.
Replace PC board.
E2, E4, E5
Check Temperature Sensor
Loose connection at port on PC board.
Tighten the connection at port on PC board.
Sensor is short-circuited.
Using multi-meter, measure resistance of the
sensor. If the resistance is < 100 ohms, change
the sensor.
PC board fault.
Replace PC board.
E6
DC Fan Motor
Operating beyond limits.
Check and correct external static pressure on
the unit.
DC motor fault.
Replace DC motor.
PC board fault.
Replace PC board.
E7
EEPROM Error (Data Storage)
Chip or PC board fault.
Replace PC board.
E9
Communication Error Between
Indoor Unit and Controller
Signal wires are short-circuited or
disconnected.
Check or reconnect signal wires.
Signal wires close to electromagnetic
source.
Distance signal wires from electromagnetic
source.
PC board fault.
Replace PC board.
Eb
EEV Error
EEV wires are short-circuited or
disconnected.
Replace EEV wires.
EEV stop.
Replace EEV
PC board fault.
Replace PC board.
Ed
Outdoor Unit Error
Outdoor unit fault.
Refer to outdoor unit troubleshooting guide.
EE
Condensate Error
Loose connection or disconnected at port
on PC board.
Tighten the connection or reconnect at port on
PC board.
Condensate switch float is stuck.
Inspect the slope.
Trap slope is too steep.
Adjust the trap slope.
Drain pipe is too long.
Adjust the length of drain pipe.
Drain pump faulty.
Replace the drain pump.
FE
No Address When Power ON for first
time
Indoor unit without address.
Run automatic addressing option at the outdoor
unit.
Use remote wireless or wired controller to
readdress indoor unit.
UU
MDC Auto System-Check Mode
MDC fault
Refer to MDC troubleshooting guide.
LEGEND
EEV
—
Electronic Expansion Valve
EEPROM
—
Electronically Erasable Programmable Read-only Memory
MDC
—
Multiport Distribution Controller
PC
—
Process Controller
MODEL
CEILING/FLOOR UNIT
R410A
HIGH
LOW
REFRIGERANT
0.44 A
15 A
0.35 A
40VMU012---3
100W (1/6HP)
320 PSIG
DESIGN
PRESSURE
580 PSIG
208/230V-1Ph-60Hz
POWER SUPPLY
MINIMUM CIRCUIT AMPACITY
FAN MOTOR
FLA
OUTPUT
MAX FUSE OR HACR BREAKER
3124627
SERIAL NO.
1616V00001
Carrier Corporation
CONFORMS TO UL STD 1995
CERTIFIED TO CSA STD.
C22. 2 No. 236
ELECTRIC CHARACTERISTICS ARE
ONLY FOR INDOOR UNIT.