A17
Hoval
Flue Gas Safety Device Trip / Sensor Fault
Boiler shows A17, burner does not start, may indicate flue gas sensor or safety device fault
Advertisements
Safety Warning
This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.
If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.
Advertisements
Possible Causes
Flue gas temperature sensor triggered, Blocked flue, Faulty flue gas sensor, Incorrect flue configuration
How to Fix / Troubleshooting
Safety: Risk of flue gas spillage. Do not operate the boiler until the cause is identified.
- Check flue terminal: Ensure the terminal is clear and correctly installed.
- Visual flue check: Look for signs of condensation leaks, corrosion, or dislodged sections. Any damage must be repaired by a qualified installer.
- Sensor inspection: Inspect the flue gas sensor wiring and mounting. Replace the sensor if it shows signs of overheating or damage.
- If the safety device has tripped due to genuine overheating, a technician must verify combustion and flue sizing before resetting or replacing components.
Advertisements
Repair Difficulty
Professional Required
5/5
Required Part
Flue Gas Temperature Sensor / Safety Thermostat
Check Price on Amazon
We may earn a commission from links on this page.
Advertisements