Display shows E13, unit may shut down during operation, often with high flue temperature

Safety: High flue temperatures can damage components and pose a safety risk. Do not ignore this error.

• 1. Check flue routing: Verify that the ACV flue system matches the installation manual (length, diameter, number of bends). Look for crushed or disconnected sections.
• 2. Inspect flue terminal: Ensure the terminal is not blocked and has adequate clearance from walls, roofs, and other structures.
• 3. Examine flue sensor: Locate the flue gas temperature sensor on the flue collector. Check wiring and connector. If the sensor is loose or not properly clipped, refit it.
• 4. Sensor test: With power off, measure the resistance of the flue sensor and compare with ACV's chart. Replace if out of range.
• 5. Check for scale/soot: Inspect the heat exchanger for heavy scale or soot that could restrict gas flow and raise flue temperature. Cleaning or replacement may be required by a professional.

If flue design is incorrect or damaged, have it redesigned or repaired by an installer familiar with ACV flue requirements.