Snap a photo — see what it is, how urgent, who to call.
One photo of the problem. fixRAgent reads it and gives you a Triage Profile.
Triage a photo nowNo sign-up.
Treat it as urgent — deal with it today. If you smell gas, do not touch switches or try to relight anything: leave, and call the gas utility or 911 from outside.
Take the photo. We’ll tell you what it is.
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Managing this for someone else? Managers: set it up for your buildings →
Managing this for someone else? There is a version of this for whole portfolios.
Managers: set it up for your buildings →“GAS HEATING LOCKOUT”
— Carrier (shareddocs.com, Carrier's literature host), Carrier 58MCB gas furnace Service and Maintenance Instructions (status codes). Codes vary by model: check your furnace’s own manual.
In plain words, 21 is about the heating circuit — an element, a relay or a safety limit in the heating path.
Carrier gives 2 other heating circuit codes for this furnace: 13 (LIMIT CIRCUIT LOCKOUT), 33 (LIMIT CIRCUIT FAULT).
Next to 21 in Carrier’s table: 14 (IGNITION LOCKOUT) and 22 (ABNORMAL FLAME-PROVING SIGNAL).
Safety: If you smell gas, do not touch switches or try to relight anything: leave, and call the gas utility or 911 from outside.
At least TODAY. fixRAgent treats this code as needing attention today. It points at water where it should not be, overheating, a combustion or ignition safety shutdown, food that may be warming, or a wiring problem. This is fixRAgent’s reading, not the manufacturer’s. A photo can raise it — water near wiring, scorch marks, a gas smell — but a code never lowers what the photo shows.
HVAC technician. Have the model and serial numbers from the label ready — a photo of the label works.
Check whether your model is under a safety recall on the U.S. Consumer Product Safety Commission’s site: cpsc.gov/Recalls. Your owner’s manual is on Carrier’s support site; search it with the model number from the label.