Carrier error codes
The complete list of Carrier fault codes shown on the display, each with what it means and the page that explains how it is diagnosed and fixed.
Carrier heating appliances display 10 documented error codes. Each code below opens its own page with the official meaning, the documented causes, the safety assessment and the parts involved.
All Carrier Error Codes
10 codes, each with its own page. Click a code to open the meaning, the documented causes and the repair.
What Fails Most Often on Carrier
Grouped from the official meaning of each of the 10 codes above — not from opinion. The number is how many different fault codes point at that component.
| Component | Codes | Examples |
|---|---|---|
| Control Board | 3 | A156, A157, A171 |
| Fan | 2 | A120, A127 |
Parts & Prices
The parts most often involved in the Carrier faults listed above.
Prices and availability vary by region and are shown by the retailer, not by TroubleAtlas.
Diagnostic Tools
What an engineer uses to work through the codes on this page.
TroubleAtlas Score — Carrier
How Carrier scores
Independently assessed across six dimensions from the documentation, the fault codes and the parts network. Based on 39 error codes across 4 appliances.
How we calculate it →TroubleAtlas Pro
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Explore TroubleAtlas Pro →Considering a New Heating System
Considering a New Heating System?
If your Carrier appliance is over 10 years old, replacing it with a modern condensing boiler or air-source heat pump could cut energy bills and remove the recurring faults listed on this page.
Compare Heating System Prices →
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