York furnace 5 red flashes: Open rollout switch
Five red flashes means a rollout switch opened. York marks it as a hard lockout rather than a one hour soft lockout, which is a deliberate distinction — this one does not release itself on a timer.
Applies to: York, Luxaire and Coleman gas furnaces using the UTEC integrated furnace control boards documented in technical service letter ST-045-09. York marks this code as a hard lockout, not a soft one.
What it means
Rollout switches sit on or near the burner assembly and open when heat appears where it should not, meaning flame escaped forward out of the burner box rather than being drawn through the heat exchanger. That indicates the combustion path is obstructed or the draft has failed, and it can produce carbon monoxide. York's table marks this code with a hard lockout notation, distinguishing it from the codes that release after an hour. That distinction is meaningful: the control is not going to retry, because retrying would put the furnace back into a condition that should not recur without someone establishing why it happened.
Most common causes
- A blocked or restricted heat exchanger.
- A blocked or partly blocked flue, forcing combustion products back toward the burners.
- A failed or weak draft inducer not pulling flame into the heat exchanger.
- A cracked heat exchanger disturbing the combustion airflow.
- Burners that are dirty, misaligned, or partly blocked.
- Insufficient combustion air in a confined furnace space.
- Overfiring, with gas pressure set too high.
How to diagnose it
- Treat this as a stop-and-call fault. Its causes are dominated by conditions that produce carbon monoxide.
- Check that carbon monoxide alarms are present and working. If any has sounded, leave and call the fire service from outside.
- Look for visible scorching, soot, or melted wire insulation near the burner compartment — from outside, without dismantling anything.
- Note whether the flue or vent termination is obviously blocked.
- Note that this is a hard lockout, so a furnace that has restarted on its own was not showing this code.
- On last-generation White-Rodgers Emerson boards this count also covers a blown on-board fuse, which is an electrical fault rather than a combustion one. Check the board part number before assuming a rollout.
How to fix it
- Turn the furnace off at its service switch and call a licensed heating technician.
- Do not press rollout switch reset buttons to restart the furnace. The switch tripped because flame went somewhere it should not.
- Have working carbon monoxide alarms on every level of the home and outside each separate sleeping area, which is what NFPA 720 and US Consumer Product Safety Commission guidance call for. That includes the level the furnace is on — basements, attics and utility spaces are where a combustion fault starts, and an alarm only on bedroom floors can miss it for a long time. This fault is one of the situations those alarms exist for.
- Every underlying cause — heat exchanger, flue, inducer, burners, gas pressure — is licensed work.
Notes
York marking this a hard lockout while marking the ignition and pressure switch lockouts as one hour soft lockouts is the manufacturer ranking its own fault codes by seriousness. That ranking is worth trusting.
Related
- 11 red flashes — Limit switch open more than five minutes — blower failure
- 3 red flashes — Pressure switch open, or first stage pressure switch open
- Which York control board you have — York used two control board generations with different code meanings
All codes for this manufacturer
York, Luxaire and Coleman furnace flash codes — every code, with what differs between models.
Not sure this is your brand?
The same count means something else on other furnaces. What 5 flashes means on every brand puts them side by side.
What the fix costs
The range here is honest but wide, because the rollout switch is the messenger, not the fault. If the cause is a blocked flue or dirty, misaligned burners, the work sits in the repair cost guide's limit-and-rollout band of $150–350 — and the guide's note on that line applies double here: you are paying to find why it tripped, not for the part. A weak inducer runs $300–900. At the far end sits the reason this code demands a proper inspection: a cracked or blocked heat exchanger runs $1,000–2,500+, which the guide calls the usual replace-the-furnace moment — at that point the replacement guide's $3,500–8,000 for a straight swap becomes the relevant number. The guide's advice on heat exchanger diagnoses applies in full: serious enough to stop running the furnace, misused often enough to deserve a second opinion with the crack shown on camera.
Fix it yourself or call a professional?
Professional, without exception — on this code the warning box above is a literal description, not boilerplate. A tripped rollout means flame left the burner box, and every documented cause is a combustion-path problem. The homeowner contribution is real but happens at arm's length: confirm the CO alarms work, switch the furnace off at its service switch, and note anything visible without opening panels — a blocked vent termination, scorch marks, a smell. The one action to specifically not take: rollout switches often carry a manual reset button, and pressing it to restart the furnace is exactly the wrong move. York marked this a hard lockout because retrying is unsafe until someone establishes why flame escaped; the reset button exists for the technician who has done that.
The same fault on other brands
Rollout gets its own code in most families: Allied's 8 flashes, Goodman's 6 flashes, and Lennox's alert 200 — which Lennox also marks as a hard lockout, the same severity call York made. Carrier is the outlier, folding rollout into its combined limit-circuit code status 33. The near-matching Goodman GMEC96 table reads its five red flashes as rollout or open fuse — the same pairing the Emerson-generation York boards use at this count, one more trace of the shared White-Rodgers lineage. The full family is indexed at rollout switch codes.
What this looks like
From the outside, this usually shows up as the furnace heats then trips out on high limit — that walkthrough covers what to check in order, and when it stops being a homeowner job.