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Lennox Furnace 349 Error Code — Meaning & Repair Cost (2026)

Integrated furnace control error — the O to R configuration link on the furnace has been cut (non-communicating mode only). Below: the most likely causes, and what the matching repair costs — Estimated national ranges with a metro localizer. Reviewed July 2026.

Code349
ApplianceLennox furnace
Brands covered1
ReviewedJuly 2026

What 349 means

Integrated furnace control error — the O to R configuration link on the furnace has been cut (non-communicating mode only).

Likely causes, most common first

  1. O-to-R jumper cut on the furnace control
  2. Resulting brownout or low voltage to the control

Base: 1 published national repair-cost guide (retrieved 2026-07) · full source registry on the methodology page · Code meaning & causes · Reviewed July 2026

What it usually costs to fix Estimated

349 on a Lennox furnace resolves to the gas furnace control board replacement problem. Lennox parts typically run ×1.35 against the mainstream baseline (Lennox 'uses proprietary parts that only Lennox dealers can source.' A direct brand comparison found a blower-motor replacement running $2,400-$2,500 installed on Lennox vs $600-$1,200 on Carrier, with Lennox parts needing to be special-ordered direct from the factory (2-4 week wait) versus same-day local-supplier availability for Carrier parts.), and the ranges below already include it.

Repair cost calculator

$270–$805 national estimate to fix the fault behind 349 (Lennox parts ×1.35). Enter a ZIP to localize.

Quality tier (adjusts parts)
National ranges — Lennox furnace control board replacement Estimated
Most common repairTypical totalDIY?
Universal control board replacement $270–$505 Pro recommended
OEM proprietary control board replacement $455–$805 Pro recommended

Plus a typical service-call / diagnostic fee of $75–$150, often credited toward the repair.

Pick a quality tier for a class-typical estimate, or a specific brand to override it (brand adjusts the parts portion only). Enter a ZIP or Canadian postal code to localize to your metro's labor costs. Everything updates without a page reload; no data leaves your browser except the shard lookup.

Base: 2 published national repair-cost guides (retrieved 2026-07) · full source registry on the methodology page · National base range (BLS OEWS May 2025 + BEA RPP 2024) · Reviewed July 2026 · Estimated

See the full gas furnace control board replacement cost guide All error codes

Codes are universal — your location changes the repair price, never the code's meaning. See the methodology for the exact localization formula and sources.

Reviewed by a Red Seal–certified appliance technician who also holds a Technical Safety BC gas ticket (Gas-C) and an ODS/halocarbon refrigerant ticket (CFC/HCFC/HFC).