Furnace Error Codes by Brand

Last updated: October 20, 2026

Four furnace brands have code pages here: Carrier, Goodman, Rheem, and Bryant/Payne. Carrier's hub explains how its two-digit flash codes are read and has pages for codes 13, 14, 33 and 34. Goodman's hub carries the code tables for ten series, from LED flash counts to three-character displays, with pages for three flashes, four flashes, and three display readings that are not faults: 9H, 1dL and F02. Rheem's hub keeps the tables for thirteen series on one page, from the two-digit displays of current furnaces to the blinking status LED of older RGRM, RGPR, RGRK and RGRA-family furnaces. The Bryant/Payne hub keeps everything on one page for the three model families that have a manufacturer document.

To find your code, note the flash pattern or the characters on the display, find the brand and series, then open the matching table. The hubs point out where one code means different things on different furnaces, which happens within a single brand more often than you would expect.

The A–Z table at the end of this page lists every furnace code page on the site.

Gas and carbon monoxide

If you smell or hear gas leaking, leave immediately. Contact your gas utility or the fire department from outside the building, and do not operate lights, phones, or other electronics before you leave. Carbon monoxide is a second hazard, and it is colorless and odorless. CPSC recommends CO alarms on every level of the home and outside sleeping areas — test them monthly — and a yearly professional inspection of every fuel-burning heating system. If a CO alarm sounds, get outside to fresh air, call 911, and do not go back inside until responders say it is safe. Symptoms of CO poisoning are headache, dizziness, weakness, nausea, vomiting, sleepiness, and confusion. These pages explain status codes and the no-tools checks the manufacturer approves; they do not tell you to open a service panel or work on gas, venting, or combustion parts. (Guidance: CPSC.)

Brands

A furnace brand is added when two conditions are met: its code tables are published in openly accessible manufacturer documentation, and there is search evidence that people look for those codes specifically. Publishing a placeholder page for a brand we cannot source would defeat the point of the section. Bryant and Payne share a parent company with Carrier but do not share one code scheme, so the Bryant/Payne hub carries its own tables read from its own documents rather than pointing at the Carrier pages.

All published code pages, A–Z

All furnace code pages on this site
Code	Brand	Name on display	Severity	DIY?
`13`	Carrier	Limit circuit lockout	Unit will not run	Licensed pro / dealer
`14`	Carrier	Ignition lockout	Unit will not run	Licensed pro / dealer
`33`	Carrier	Limit circuit fault	Runs with warning	Check, then call
`34`	Carrier	Ignition proving failure	Runs with warning	Check, then call
`1dL`	Goodman	Idle	Not a fault	No action needed
`3 flashes`	Goodman	Pressure switch stuck open	Unit will not run	Check, then call
`4 flashes`	Goodman	Open limit switch	Unit will not run	Check, then call
`9H`	Goodman	Gas heat - Single Stage Control	Not a fault	No action needed
`F02`	Goodman	Blower Speed Number	Not a fault	No action needed