21
Table 6 — Troubleshooting
Replacement Parts —
Quote the unit type 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. 43.
DIGITAL
DISPLAY
DESCRIPTION
POSSIBLE CAUSES
POSSIBLE SOLUTIONS
dd
Heating/Cooling Mode Conflict
System is in cooling or fan mode only and heating
signal is received from a unit in 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 and Outdoor Unit
Signal wires are short-circuited or disconnected.
Check or reconnect signal wire.
Signal wires 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
Check 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.
Check or reconnect signal wire.
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 Overflow
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 float.
Trap slope is too steep.
Adjust the trap slope.
Drain pipe is too long.
Adjust the length of the drain pipe.
Drain pump faulty.
Replace the drain pump.
FE
No Address When Powered
ON For First Time
Indoor unit without address.
Run automatic addressing option at outdoor
unit.
Use remote wireless or wired controller to
readdress the indoor unit.
UU
MDC In Auto System-Check
Mode
MDC Fault.
Refer to MDC troubleshooting guide.
LEGEND:
EEPROM
— Electronically Erasable Programmable Read-only Memory
EEV
— Electronic Expansion Valve
MDC
— Multiport Distribution Controller
PC
— Process Controller
ONE-WAY CASSETTE
AIR CONDITIONER INDOOR UNIT
MODEL
R410A
HIGH
LOW
REFRIGERANT
250 PSIG
650 PSIG
DESIGN
PRESSURE
POWER SUPPLY
MINIMUM CIRCUIT AMPACITY
MAX FUSE OR HACR BREAKER
FAN MOTOR
FLA
OUTPUT
CONFORMS TO UL STD. 1995
CERTIFIED TO CSA STD.
C22. 2 No. 236
ELECTRIC CHARACTERISTICS ARE
ONLY FOR INDOOR UNIT.
SERIAL NO.
Carrier Corporation
40VMI005---A
0.29A
15 A
0.23 A
208/230V-1Ph-60Hz
20W (1/30HP)
Fig. 43 — Unit Serial Plate (Example)
