York Error Code R3: Pressure Switch Stuck Open
How to Fix York Code R3
- Step 1: Check the furnace vent outside your home for any visible obstructions like snow, ice, or leaves. Safely clear any blockages you can reach.
- Step 2: Ensure that all return air vents are unblocked and clean. A lack of airflow can cause the furnace to overheat and shut down.
- Step 3: If the error persists after checking the vents, contact a qualified HVAC technician to diagnose and repair the furnace.
How to Reset York Code R3
- Turn off the furnace power switch, usually located on or near the unit.
- Turn off the circuit breaker for the furnace. Wait 30 seconds.
- Restore power at the breaker and flip the furnace switch back on.
- Set the thermostat to call for heat. If the error code returns after 2-3 ignition attempts, the fault requires repair.
Resetting clears the code from the display but does not fix the underlying fault. If the code returns after reset, proceed to the diagnostic steps above.
What Does York Error Code R3 Mean?
The R3 error code on your York furnace indicates that the pressure switch is stuck in the open position. This switch is a safety device that verifies the furnace's exhaust fan (inducer motor) is working correctly before allowing the burners to ignite. When the inducer motor starts, it creates a slight vacuum that closes the pressure switch, signaling to the control board that it's safe to start the ignition sequence. If the switch remains open, the furnace control board will prevent ignition and display the R3 error. This is a safety feature to prevent the furnace from operating improperly, which could lead to a dangerous buildup of exhaust gases inside your home.
Common Causes
- Blocked vent pipe: Obstructions like snow, ice, leaves, or debris can prevent the inducer motor from creating enough vacuum to close the pressure switch.
- Failed inducer motor: A weak or failing inducer motor may not generate sufficient vacuum to activate the pressure switch.
- Faulty pressure switch: The pressure switch itself may be defective and not closing even when the correct vacuum is present.
- Blocked or kinked pressure switch tubing: The small tube connecting the inducer motor to the pressure switch can become blocked or kinked, preventing the vacuum from reaching the switch.
- Condensate blockage: Excessive condensate buildup in the furnace can block the vent or pressure switch tubing.
Diagnostic Steps
| If... | Check | Expected |
|---|---|---|
| Furnace displays R3 error | Manually check pressure switch with multimeter for continuity (ohms) with inducer fan running | Should show continuity (near 0 ohms) when inducer is on. |
| Pressure switch shows open circuit with inducer running | Disconnect tubing from pressure switch and measure vacuum at the inducer port with a manometer | Should read vacuum within manufacturer's specification (e.g., -0.5" WC). |
| Vacuum is within spec but switch remains open | Inspect the pressure switch tubing for kinks, cracks, or blockage | Tubing should be clear and unobstructed. |
| Vacuum is low | Inspect inducer motor for proper voltage. Use multimeter to measure voltage at inducer motor terminals. | Voltage should match the motor's nameplate rating (e.g., 120 VAC). |
Applicable York Models
Replacement Parts
| Part | OEM Number | Est. Cost | Where to Buy |
|---|---|---|---|
| Pressure Switch | 024-36370-000 | — | Find Part |
| Inducer Motor | S1-02435933000 | — | Find Part |
| Pressure Switch Tubing | — | — | — |
Related Codes on Same Models
Other codes that affect the same York model families as R3.
| Code | Description | Severity |
|---|---|---|
| A4 | Improper Thermostat Wiring | Warning |
| AF | Low Flame Current | Critical |
| R1 | Flame Without Call | Critical |
| R2 | Pressure Switch Stuck Closed | Warning |
| R4 | High Limit Switch Open | Warning |
| R5 | Rollout Switch Open | Critical |
| R6 | Gas Valve Failure | Critical |
| R7 | Ignition Lockout | Critical |
| R9 | Reversed Polarity | Critical |