Emerson AE8-1385 Manuel D’Utilisation

10

© 2011 Emerson Climate Technologies
Printed in the U.S.A.

Application Engineering

B

U

L

L

E

T

I

N

Solid Green “RUN” Module has power and 

operating normally

Supply voltage is present at module terminals

Solid Red “TRIP”

Thermostat demand signal Y is 

present, but the compressor is 

not running

1.   Compressor protector is open 

•  Check for high head pressure
•  Check compressor supply voltage 

2.  Outdoor unit power disconnect is open 
3.  Compressor circuit breaker or fuse(s) is open 
4.  Broken wire or connector is not making contact 
5.  High pressure switch open if present in system 
6.  Compressor contactor has failed open

Yellow “ALERT” 

Flash Code 1

Low Refrigerant Charge 

Compressor is running extremely 

long run cycles

1.  Low refrigerant charge 
2.  Evaporator blower is not running

•  Check blower relay coil and contacts
•  Check blower motor capacitor
•  Check blower motor for failure or blockage
•  Check evaporator blower wiring and connectors 
•  Check indoor blower control board
•  Check thermostat wiring for open circuit 

3.  Evaporator coil is frozen

•  Check for low suction pressure 
•  Check for excessively low thermostat setting
•  Check evaporator airfl ow (coil blockages or return air fi lter)
•  Check ductwork or registers for blockage 

4.  Faulty metering device 

•  Check TXV bulb installation (size, location and contact) 
• Check if TXV/fi xed orifi ce is stuck closed or defective 

5.  Liquid line restriction (fi lter drier blocked if present in system) 
6.  Thermostat is malfunctioning

•  Check thermostat sub-base or wiring for short circuit 
•  Check thermostat installation (location, level) 

Yellow “ALERT” 

Flash Code 2

High Refrigerant Charge 

Discharge pressure out of limits 

or compressor overloaded

1.  Condenser fan is not running

•  Check fan capacitor
•  Check fan wiring and connectors
•  Check fan motor for failure or blockage 

2.  High head pressure

•  Check high pressure switch if present in system
•  Check if system is overcharged with refrigerant 
•  Check for non-condensable in system 

3.  Condenser coil poor air circulation (dirty, blocked, damaged) 
4.  Return air duct has substantial leakage

Yellow “ALERT” 

Flash Code 3

Compressor is running only 

briefl y due to pressure switch 

cycling

1.  Time delay relay or control board defective 
2.  If high pressure switch present go to Flash Code 2 information

Flash Code number corresponds to the number of LED fl ashes, followed by a pause and then repeated. 
TRIP and ALERT LEDs fl ashing at same time means control circuit voltage is too low for operation (brown-out conditions).