Your furnace is flashing a code.
Here's what it means.
Brand-specific HVAC error codes decoded: ranked causes, safe DIY checks, honest repair costs, and when to call a licensed technician.
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Carrier 5 codes Goodman 3 codes Trane 1 code Lennox 1 code Rheem 1 code Bryant 2 codes Honeywell 1 code
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Bryant Furnace — Code 33 Bryant Furnace Code 33: Meaning, Causes & Fixes Bryant furnace Code 33 means a limit or flame rollout switch tripped. Causes, safe checks, and pro repair costs from $0 to $600. Carrier Furnace — Code 13 Carrier Furnace Code 13: Meaning, Causes & Fixes Carrier furnace Code 13 means a limit circuit lockout. Causes: dirty filter, blocked vents, bad blower. Fixes cost $0 DIY to $600+. Carrier Air Conditioner — Not cooling Carrier AC Not Cooling: Causes, Fixes & Repair Costs Carrier AC not cooling? Causes include dirty filters, low refrigerant, failed capacitors and frozen coils. DIY checks plus repair costs from $0 to $2,500+. Bryant Furnace — Code 13 Bryant Furnace Code 13: Meaning, Causes & Fixes Bryant furnace Code 13 means a limit circuit lockout. Learn causes, safe checks, technician diagnosis and repair costs from $0 DIY to $600. Carrier Furnace — Code 31 (pressure switch) Carrier Furnace Code 31: Causes, Fixes & Costs Carrier furnace flashing code 31 (pressure switch/inducer fault)? What it means, causes ranked by likelihood, safe checks, and repair costs. Carrier Furnace — Code 33 Carrier Furnace Code 33: Causes, Fixes & Costs Carrier furnace flashing code 33 (limit circuit fault)? What it means, the causes ranked by likelihood, safe checks you can do, and repair costs. Goodman Furnace — Flame rollout / burning smell Goodman Furnace Flame Rollout: Shut Down Now Goodman furnace flame rollout switch tripped or a burning smell? Why this is an emergency, what to do right now, the CO risk, and repair costs. Goodman Air Conditioner — Not cooling / no codes Goodman AC Running But Not Cooling: Causes & Costs Goodman air conditioner running but not cooling the house? The causes ranked by likelihood, safe checks you can do, and honest repair costs. Carrier Furnace — Code 34 Carrier Furnace Code 34: Ignition Proving Failure & Fixes Carrier furnace Code 34 means ignition proving failure. Causes, safe checks and pro fixes — flame sensor, gas valve, $0 DIY to $600 repair. Goodman Furnace — Lockout (no heat) Goodman Furnace Lockout: Causes, Fixes & Costs Goodman or Amana furnace in ignition lockout with no heat? What it means, causes ranked, the dirty flame sensor fix, safe checks, and repair costs. Honeywell Thermostat — Blank screen / no power Honeywell Thermostat Blank Screen: Fixes & Costs Honeywell thermostat blank or dead with no power? The causes ranked by likelihood, safe DIY fixes you can do today, and what it costs if you call a pro. Lennox Furnace — Code 200 (ignition lockout) Lennox Furnace Code 200: Causes, Fixes & Costs Lennox furnace showing code 200 ignition lockout with no heat? What it means, causes ranked, the flame-sensor fix, safe checks, and real repair costs.Looking for a specific code? Search the full library or browse furnaces, air conditioners and heat pumps.