York Error Code R9: Reversed Polarity

Severity
Critical
Type
digital display
Estimated repair cost: $300 — $650 (parts + labor)
Warning: This error indicates a dangerous electrical wiring problem. Immediately shut off the furnace at the breaker and call a qualified HVAC technician or electrician.

How to Fix York Code R9

  1. Step 1: Immediately turn off the furnace at the circuit breaker to eliminate the electrical hazard.
  2. Step 2: Do not attempt to restart the furnace or troubleshoot the wiring yourself.
  3. Step 3: Contact a licensed HVAC technician or qualified electrician to inspect and correct the wiring issue.

How to Reset York Code R9

  1. Turn off the furnace power switch, usually located on or near the unit.
  2. Turn off the circuit breaker for the furnace. Wait 30 seconds.
  3. Restore power at the breaker and flip the furnace switch back on.
  4. Set the thermostat to call for heat. If the error code returns after 2-3 ignition attempts, the fault requires repair.

What does R9 mean?

The R9 error code on your York furnace indicates a reversed polarity issue. This means the hot and neutral wires are connected incorrectly somewhere in the electrical circuit powering your furnace. This is a serious safety hazard because it can energize the metal parts of the furnace, creating a risk of electric shock. It can also damage the furnace's control board and other components.

Your York furnace relies on proper electrical polarity to operate safely and reliably. When the polarity is reversed, the furnace's safety mechanisms may not function correctly, potentially leading to a fire or explosion. Do not attempt to troubleshoot this issue yourself. Contact a qualified professional immediately.

Affected Models

Replacement Parts

PartOEM NumberEst. Cost
Integrated Furnace Control (IFC) Board S1-33102948000
Wiring Harness
Electrical Outlet

Related Codes on Same Models

CodeDescriptionSeverity
R1 Flame Without Call Critical
R2 Pressure Switch Stuck Closed Warning
R3 Pressure Switch Stuck Open Warning
R4 High Limit Switch Open Warning
R5 Rollout Switch Open Critical
R6 Gas Valve Failure Critical
R7 Ignition Lockout Critical
A4 Improper Thermostat Wiring Warning
AF Low Flame Current Critical