Fault code decoder

Type a code (such as 33, E110, H6 or 4 flashes) or a word from the meaning (such as pressure or flame). Pick your brand to avoid mixing up codes. Results come only from manufacturer documents; each result links to its code table and states the source.

Why choose your brand first?

The same code means different things on different equipment. Carrier status code 33 is a limit circuit fault on a furnace, while Trane 4 flashes is an open temperature limit circuit on a different control board, and H6 is a compressor start-up failure on Daikin mini-splits. Filtering by equipment avoids false matches.

Not found?

If your code is not here, we have not confirmed it in a manufacturer document, and we will not guess. Check your owner's manual or the service label on your equipment. For furnace lights, see how to read furnace blinking light codes.