Carrier · error code

Carrier Air-conditioner 18-11 Error Code — Meaning & Repair Cost (2026)

Indoor coil freeze protection — the control is reducing compressor speed because saturated suction temperature is approaching 32°F and ice is likely to form on the indoor coil. Below: the most likely causes, and what the matching repair costs — Estimated national ranges with a metro localizer. Reviewed July 2026.

Code18-11
ApplianceCarrier air-conditioner
Brands covered1
ReviewedJuly 2026

What 18-11 means

Indoor coil freeze protection — the control is reducing compressor speed because saturated suction temperature is approaching 32°F and ice is likely to form on the indoor coil.

Likely causes, most common first

  1. Dirty air filter or restrictive ductwork starving the indoor coil of airflow
  2. Low refrigerant charge

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

18-11 on a Carrier air-conditioner resolves to the central air conditioning frozen evaporator coil problem. Carrier parts typically run ×1.15 against the mainstream baseline (Same engineering platform as sister brands Bryant/Payne (same compressors, control boards, blower motors, contactors, run capacitors per a parts-focused comparison), but sold through Carrier's more selective Factory Authorized Dealer network; a brand cost-comparison piece puts Carrier at roughly 10-20% more for the same underlying hardware than sister brand Bryant.), and the ranges below already include it.

Repair cost calculator

$105–$1,060 national estimate to fix the fault behind 18-11 (Carrier parts ×1.15). Enter a ZIP to localize.

Quality tier (adjusts parts)
National ranges — Carrier air-conditioner frozen evaporator coil Estimated
Most common repairTypical totalDIY?
Airflow fix (filter change / blower/duct restriction cleared) $105–$315 DIY possible
Refrigerant recharge (low charge causing the freeze) $315–$975 Pro recommended
Coil cleaning / minor coil repair (frost/ice damage to fins) $415–$1,060 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 central air conditioning frozen evaporator coil 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).