Furnace rollout switch codes: why it tripped

A rollout switch is the one fault code on a furnace that should never be reset and rerun without finding the cause. Here is what it means on each brand.

What the rollout switch does

Rollout switches are manual-reset thermal limits mounted at the burner opening, outside the combustion chamber. They trip when flame or hot gas rolls out of the burner box toward the front of the furnace instead of being drawn through the heat exchanger and up the flue. Most are one-time manual reset by design, so that a tripped rollout cannot clear itself and hide.

Why one part produces several different codes

A rollout trip means combustion products went somewhere they should not. The usual causes are a blocked or restricted heat exchanger, a cracked heat exchanger, a blocked flue or vent, a failed inducer, or a burner problem sending flame forward. On some controls the same flash count also covers a blown control module fuse, so the code alone does not always mean rollout — check which model the code table applies to.

Every rollout switch code on this site

8 codes across 7 control families. The meaning is the manufacturer's, from the document listed at the foot of each code page.

Brand	Code	What it reports
Armstrong	8 flashes	Rollout switch open
Carrier	Status code 33	Limit circuit fault — a limit or flame rollout switch is open
Goodman	6 flashes	Rollout switch has tripped
Goodman	6 flashes	Rollout limit open, or control module fuse blown
Goodman	Ed	Rollout switch has tripped
Goodman	5 red flashes	Open rollout switch, or open fuse detected
Lennox	Alert code 200	Rollout limit switch open
York	5 red flashes	Open rollout switch

Before you work on it

This is the code most directly associated with carbon monoxide entering the living space. Resetting a rollout switch and running the furnace without finding why it tripped can put combustion products into the house. It needs a licensed technician, and a working CO alarm on every level including the one the furnace is on.

Other parts

Sources

Every code meaning above comes from the manufacturer document behind its code page:

This site is a reference, not a substitute for a licensed HVAC technician. Gas appliances can leak carbon monoxide and cause fire. Anything involving gas lines, the heat exchanger, or the flame sensing circuit should be handled by a licensed professional. Pages are written with AI assistance from the sources listed on each page and checked against them before publishing.