York error codes
26 documented codes with ranked causes, repair costs, and step-by-step guidance.
York heat pump code chart (5) York furnace code chart (21)
York Heat Pump — Stuck in defrost mode York Heat Pump Stuck in Defrost Mode: Causes & Fixes York heat pump stuck in defrost? Learn the causes (sensor, board, reversing valve, relay), safe checks, technician fixes, and repair costs. York Heat Pump — Frozen and not defrosting York Heat Pump Frozen, Not Defrosting: Causes & Fixes York heat pump iced up and not defrosting? Learn the causes (defrost board, sensor, reversing valve, low charge), safe checks, and repair costs. York Heat Pump — Ice on outdoor unit York Heat Pump Ice on Outdoor Unit: Causes & Fixes Why ice builds on a York heat pump outdoor unit: normal frost, roof runoff, airflow, low charge or defrost faults. Safe checks, pro fixes and repair costs. York Heat Pump — Not cooling York Heat Pump Not Cooling: Causes, Fixes & Costs York heat pump not cooling? Learn the likely causes (filter, thermostat, refrigerant, capacitor, reversing valve), safe checks, and repair costs. York Heat Pump — Not heating York Heat Pump Not Heating: Causes, Fixes & Costs York heat pump not heating? Common causes like thermostat setup, defrost, low refrigerant and failed reversing valve, safe checks, and repair costs. York Furnace — Pressure switch stuck open York Furnace Pressure Switch Stuck Open: Causes & Fixes York furnace pressure switch stuck open: blocked vents, condensate, or a weak inducer. Diagnosis, fixes and $0 DIY to $1,200+ repair costs. York Furnace — Leaking water York Furnace Leaking Water: Causes, Fixes & Costs York furnace leaking water? Common causes include clogged condensate drains, cracked traps and flue issues—plus DIY checks and real US repair costs. York Furnace — Runs constantly but not enough heat York Furnace Runs Constantly But Not Enough Heat: Fixes York furnace runs nonstop but won't warm your home? Causes include dirty filters, duct losses, staging faults & heat exchanger problems. Fixes $0 DIY–$3,500+. York Furnace — Blower not running York Furnace Blower Not Running: Causes & Fixes York furnace blower not running? Causes from blower motor to control board, plus DIY checks and repair costs from $0 to $1,500+. York Furnace — Blower won't shut off York Furnace Blower Won't Shut Off: Causes & Fixes York furnace blower runs constantly? Causes include thermostat fan settings, a stuck fan relay or bad limit switch. Fixes and costs from $0 DIY to $1,800. York Furnace — Blowing cold air York Furnace Blowing Cold Air: Causes, Fixes & Costs York furnace blowing cold air? Causes from thermostat fan settings to flame-proving faults, plus fixes and repair costs from $0 DIY to $1,200. York Furnace — Ignition lockout York Furnace Ignition Lockout: Causes, Fixes & Costs York furnace ignition lockout causes include a dirty flame sensor, weak igniter and low gas pressure. See safe checks, fixes and typical repair costs. York Furnace — Flame sensor problems York Furnace Flame Sensor Problems: Causes & Fixes York furnace flame sensor problems cause short cycling and ignition lockout. Learn the causes, fixes and repair costs ($80 diagnostic – $800+ with a board). York Furnace — Keeps shutting off York Furnace Keeps Shutting Off: Causes & Fixes York furnace keeps shutting off? Flame sensor, limit, pressure switch & flue causes, safe DIY checks, and repair costs from $0 to $1,200. York Furnace — Loud bang on startup York Furnace Loud Bang on Startup: Causes & Fixes A loud bang when your York furnace starts usually means delayed ignition or expanding ductwork. Causes, fixes and repair costs explained. York Furnace — Short cycling York Furnace Short Cycling: Causes, Diagnosis & Fixes York furnace short cycling? Causes range from a clogged filter to a failing flame sensor or limit. DIY checks plus repair costs $0-$2,500+. York Furnace — Won't turn on York Furnace Won't Turn On: Causes, Fixes & Costs York furnace won't turn on? Causes from no power, dead thermostat, blown fuse or bad door switch, plus fixes and repair costs from $0 DIY to $1,100. York Furnace — 10 flashes York Furnace 10 Flashes: Gas Valve Circuit Error Fixes York furnace 10 flashes means the gas valve is energized with no call for heat. Gas-safety steps, causes, safe checks, and repair costs. York Furnace — Won't ignite York Furnace Won't Ignite: Causes, Diagnosis & Fixes Why a York furnace won't ignite: bad igniter, flame sensor, gas or pressure issues, plus safe checks, tech diagnosis and repair costs ($0–$1,200+). York Furnace — 2 flashes York Furnace 2 Flashes: Pressure Switch Stuck Closed York furnace 2 flashes means the pressure switch is closed with the inducer off. Causes, safe checks, and $0–$400 repair costs. York Furnace — 3 flashes York Furnace 3 Flashes: Pressure Switch Open Causes & Fixes York furnace 3 flashes means pressure switch open with inducer on. Causes: blocked vent, clogged condensate, bad switch. Fixes $0–$1,200. York Furnace — 4 flashes York Furnace 4 Flashes: Open Limit Switch Causes & Fixes York furnace 4 flashes means an open high-limit switch from restricted airflow or overheating. Causes, safe checks, fixes and $10–$1,500+ costs. York Furnace — 5 flashes York Furnace 5 Flashes: Flame Sensed With Gas Off York furnace 5 flashes means flame sensed with the gas valve off. Causes, safe checks, tech diagnosis and repair costs from $0 DIY to $1,200. York Furnace — 6 flashes York Furnace 6 Flashes: Pressure Switch Cycle Lockout York furnace 6 flashes means pressure switch cycle lockout. Causes, safe checks, fixes and repair costs from $0 DIY to $1,200.