What It Means
- CBK45UHPT, CBK45UHVT: Sensor indicates fault
- Long Run Time - Compressor is running extremely long run cycles.
- EL18KSLV: EEPROM malfunction
Lennox Split & Multi-Split
Lennox Split & Multi-Split Error Code 1
Split & Multi-Split
1 means different things on different Split & Multi-Split models. Enter your model number to see only your reading, or find your model below.
Causes & actions from Lennox
Sensor indicates fault
Models: CBK45UHPT, CBK45UHVT
Air handler (indoor)
How it shows
- rds noncomm red flash led: 1 (red: flashing ×1)
Replace the sensor
Other manual wording
CBK45UHPT, CBK45UHVT
Replace the sensor (Cat. # 26Z69)
Applicable models & manual sources
- CBK45UHPT
Sensor indicates fault
- CBK45UHVT
Sensor indicates fault
- CBK45UHVT
Sensor indicates fault
- CBK45UHPT
Sensor indicates fault
- CBK45UHVT
Sensor indicates fault
- CBK45UHVT
Sensor indicates fault
Long Run Time - Compressor is running extremely long run cycles.
4 models
HSXB15, XC15, XP15, XP19
How it shows
- lsom alert led: 1 (alert: flashing ×1)
1Low refrigerant charge. 2Evaporator blower is not running. (cid:4) Check blower relay coil and contacts (cid:4) Check blower motor capacitor (cid:4) Check blower motor for failure or blockage (cid:4) Check evaporator blower wiring and connectors (cid:4) Check indoor blower control board (cid:4) Check thermostat wiring for open circuit 3Evaporator coil is frozen. (cid:4) Check for low suction pressure (cid:4) Check for excessively low thermostat setting (cid:4) Check evaporator airflow (coil blockages or return air filter) (cid:4) Check ductwork or registers for blockage. 4Faulty metering device. (cid:4) Check TXV bulb installation (size, location and contact) (cid:4) Check if TXV/fixed orifice is stuck closed or defective 5Condenser coil is dirty. 6Liquid line restriction (filter drier blocked if present). 7Thermostat is malfunctioning. (cid:4) Check thermostat sub−base or wiring for short circuit (cid:4) Check thermostat installation (location and level)
Other manual wording (1 of 2)
XC15, XP15
1Low refrigerant charge. 2Evaporator blower is not running. 3Evaporator coil is frozen. 4Faulty metering device. 5Condenser coil is dirty. 6Liquid line restriction (filter drier blocked if present). 7Thermostat is malfunctioning.
Other manual wording (2 of 2)
HSXB15
1 Low refrigerant charge. 2 Evaporator blower is not running. 3 Evaporator coil is frozen. 4 Faulty metering device. 5 Condenser coil is dirty 6 Liquid line restriction (filter drier blocked if present) 7 Thermostat is malfunctioning.
Applicable models & manual sources
- XP19
Long Run Time − Compressor is running extremely long run cycles.
- XP19
Long Run Time − Compressor is running extremely long run cycles.
- XC15
Long Run Time − Compres- sor is running extremely long run cycles
- XP15
Long Run Time − Compres- sor is running extremely long run cycles
- HSXB15
Long Run Time Compressor is running extremely long run cycles
EEPROM malfunction
Models: EL18KSLV
Heat pump (outdoor)
How it shows
- el18kslv outdoor fault display: 1
- el18kslv pcb fault led: 1
EEPROM chip damaged or data wrong or related circuit damaged
Applicable models & manual sources
- EL18KSLV
EEPROM malfunction
Disclaimer: This information is for general reference. Code wording and instructions vary by model. Always follow the service manual for your exact unit.
What should you check next?
Continue in ACLogics with guided diagnosis for your equipment and symptoms.
