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Model reference

Lennox CBX40UHV

HVAC

2 documents29 error codes4 service modes

Available documentation

Service Manual

  • INSTALLATION AND SERVICE PROCEDURE - CBX40UHV (HFC-410A) SERIES UNITS (iComfort-enabled)60 pg
    Covers this model

Installation Guide

  • Dave Lennox Signature Collection CBX40UHV Units Installation Instructions40 pg
    Covers this model
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Error codes (29)

CodeMeaning
101The air-handler has lost communication with the rest of the system.102There is a frequency/distortion problem with the power to the air-handler.103The 24VAC to the air-handler control is lower than the required range of 18 to…104There is a delay in the air-handler responding to the system.105The iComfort thermostat has lost communication with the air-handler for more…106There is a hardware problem with the air-handler control.130An air-handler configuration jumper is missing.131The air-handler control parameters are corrupted.132The air-handler control software is corrupted.133The iComfort thermostat has found a problem with the air-handler outdoor sensor.201The system has lost communication with the air-handler indoor blower motor.202The unit size code for the air-handler and the size of blower motor do not…203The unit size code for the air-handler has not been selected.204The air-handler's blower motor will not start.205The indoor blower motor is overheating (motor tripped on internal protector).206There is a problem with the air-handler discharge air sensor.207The blower cannot provide the requested CFM due to high static (cutback mode).208The indoor and outdoor unit capacities do not match.301The O relay on the air-handler has failed (pilot relay contacts did not close…302The R to O jumper was not removed on the air-handler control board.303The Y1 relay on the air-handler has failed (pilot relay contacts did not close…304The Y2 relay on the air-handler has failed (pilot relay contacts did not close…350The air-handler's electric heat is not configured.351There is a problem with the air-handler's first stage electric heat (pilot…352There is a problem with the air-handler's second stage electric heat (pilot…353There is a problem with the air-handler's third stage electric heat (pilot…354There is a problem with the air-handler's fourth stage electric heat (pilot…355There is a problem with the air-handler's fifth stage electric heat (pilot…401The secondary voltage for the air-handler has fallen below 18VAC; if this…

Service modes (4)

  • Configuring Unit Size Codes1
  • Configuring/Detecting Electric Heat Sections1
  • Error Code Recall Mode1
  • Indoor Blower Test Mode1

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