Control shows 'Sensor Short' or similar for a specific temperature sensor; reading may show extremely high temperature.

Safety first: Turn off power before handling wiring.

• Identify the sensor: Determine which sensor (inlet, outlet, flue, tank) is reported as shorted.
• Inspect connectors: Disconnect the sensor and check for moisture, corrosion, or debris in the plug. Dry and clean as needed.
• Check cable for damage: Look along the cable for crushed sections, cuts, or melted insulation that could cause a short. Repair or replace as necessary.
• Test with meter: With the sensor disconnected, measure resistance. A reading near zero ohms indicates a shorted sensor; replace it.
• Replace sensor: Install a new OEM sensor and secure wiring away from hot or sharp surfaces.