What It Means
- XP19: LED is on but system and compressor check OK.
- XP19: Thermostat demand signal Y1 is present, but compressor not running
Lennox Split & Multi-Split
Lennox Error Code Red LED ON
Split & Multi-Split
Red LED ON 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
LED is on but system and compressor check OK.
Models: XP19
How it shows
- lsom trip led: Red LED ON (trip: on)
1Verify Y terminal is connected to 24VAC at contactor coil. 2Verify voltage at contactor coil falls below 0.5VAC when off. 3Verify 24VAC is present across Y and C when thermostat demand signal is present; if not present, R and C wires are reversed.
Applicable models & manual sources
- XP19
LED is on but system and compressor check OK.
- XP19
LED is on but system and compressor check OK.
Thermostat demand signal Y1 is present, but compressor not running
Models: XP19
How it shows
- lsom trip led: Red LED ON (trip: on)
1Compressor protector is open. (cid:4) Check for high head pressure (cid:4) Check compressor supply voltage 2Outdoor unit power disconnect is open. 3Compressor circuit breaker or fuse(s) is open. 4Broken wire or connector is not making contact. 5Low or high pressure switch open if present in the system. 6Compressor contactor has failed to close.
Applicable models & manual sources
- XP19
Thermostat demand signal Y1 is present, but compressor not running
- XP19
Thermostat demand signal Y1 is present, but compressor not running
Disclaimer: This information is for general reference. Code wording and instructions vary by model. Always follow the service manual for your exact unit.
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