Lennox · error code

Lennox Heat-pump 416 Error Code — Meaning & Repair Cost (2026)

Outdoor coil sensor is open, shorted or out of range; the outdoor control will not perform demand or time/temperature defrost. Below: the most likely causes, and what the matching repair costs — Estimated national ranges with a metro localizer. Reviewed July 2026.

Code416
ApplianceLennox heat-pump
Brands covered1
ReviewedJuly 2026

What 416 means

Outdoor coil sensor is open, shorted or out of range; the outdoor control will not perform demand or time/temperature defrost.

Likely causes, most common first

  1. Failed outdoor coil temperature sensor
  2. Sensor harness not plugged in correctly

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

416 on a Lennox heat-pump resolves to the heat pump stuck in defrost / frozen outdoor unit 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

$155–$1,675 national estimate to fix the fault behind 416 (Lennox parts ×1.35). Enter a ZIP to localize.

Quality tier (adjusts parts)
National ranges — Lennox heat-pump stuck in defrost / frozen outdoor unit Estimated
Most common repairTypical totalDIY?
Defrost control board replacement $210–$740 Pro recommended
Defrost sensor / outdoor coil thermostat replacement $155–$435 Pro recommended
Reversing valve replacement $455–$1,675 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 heat pump stuck in defrost / frozen outdoor unit 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).