Error code reference

Lennox Furnace Error Code E349

No 24 Volts between R & O on integrated control with non-communicating outdoor unit (dual fuel module…

No 24 Volts between R & O on integrated control with non-communicating outdoor unit (dual fuel module required for heat pump application).

First step from the service manual

Configuration link R to O needs to be restored. Replace link or hard-wire.

The complete diagnostic procedure includes additional test steps, resistance specifications, wiring diagram references, and component test points.

MyPros+ Max

Get the full diagnostic procedure for E349.

  • Step-by-step tests with expected resistance, voltage, and continuity values
  • Wiring diagram references and connector pinouts from the OEM service manual
  • Verified part numbers when replacement is required
Get the full procedure

$29/month · Cancel anytime · Or $9.95 3-day pass

78,000+ service manuals · 160,000+ error codes · 55+ brands

Get Started

$29/month · Cancel anytime · Or $9.95 3-day pass