Fault Code Lookup

HVAC Sales Master
b1
Integrated control module has lost communications with circulator blower motor
This code typically points to
  • Loose wiring connection at blower motor control leads
  • Failed circulator blower motor
  • Failed integrated control module

Next checks to confirm
  1. Tighten/correct wiring
  2. Check blower motor and replace if necessary
  3. Check integrated control module and replace if necessary

Escalation
Furnace fails to operate
Reset behavior
Clears after blower communication path is restored.
Urgent
Fix now
Source
DC96VC/DM96VC Service Instructions troubleshooting chart, p.48