Saunier Duval Repair Service in Fletton and Woodston

What does error code 14 mean on a Saunier Duval Themaclassic boiler?

Error 14 on a Saunier Duval Themaclassic boiler indicates the central heating flow temperature has exceeded the maximum safe limit. This is a temperature control issue. Contact a Gas Safe registered engineer.

What does error F6 mean on a Saunier Duval Condens boiler?

Error F6 on a Saunier Duval Condens boiler indicates a central heating flow thermistor fault. The temperature sensor or its wiring may be defective. Switch off the boiler and contact a Gas Safe registered engineer to inspect and replace the thermistor if necessary.

What does error code 10 mean on a Saunier Duval Themaclassic boiler?

Error 10 on a Saunier Duval Themaclassic boiler indicates a central heating return NTC sensor fault. The sensor cable may be defective or disconnected. Switch off the boiler and contact a qualified heating engineer.

What does error F12 mean on a Saunier Duval Condens boiler?

Error F12 on a Saunier Duval Condens boiler indicates a user interface or main board reception fault. The display unit is not communicating correctly with the main circuit board. Switch off the boiler and contact a Gas Safe registered engineer to inspect the connections and components.

What does error F28 mean on a Saunier Duval Condens boiler?

Error F28 on a Saunier Duval Condens boiler indicates a permanent drift between flow and return sensors. A thermistor may be defective. Contact a Gas Safe registered engineer to test and replace the sensors.

How do I set my Saunier Duval boiler for a holiday or extended absence?

If you have a programmable thermostat or controller, use the holiday mode function to maintain a low temperature while you are away. If your thermostat does not have a holiday mode, simply lower the room thermostat to a minimum setting that prevents freezing, typically around 10°C. Keep the boiler powered on so frost protection remains active. Never turn off the gas supply during cold weather as this disables frost protection.

Why does my Saunier Duval boiler provide hot water but not heating?

The most common causes are: the boiler may be set to summer mode (hot water only), the room thermostat may be set too low, thermostatic radiator valves may be turned down or off, or there may be a fault with the diverter valve (3-way valve) which directs hot water between the heating circuit and hot water outlet.

How can I improve the efficiency of my Saunier Duval boiler?

Maintain correct system pressure (1-1.5 bar cold), bleed radiators regularly to remove trapped air, set heating and hot water temperatures appropriately for your needs rather than at maximum, and ensure the boiler is serviced annually. Use the summer mode during warmer months when heating is not required. Keep the area around the boiler clear for proper ventilation.

How do I reset my Saunier Duval boiler after a fault?

For most Saunier Duval boilers, turn the control to the off position (marked "0" on many models), wait 5 seconds, then turn it back to the on position ("I"). For newer models with a dedicated reset button, simply press the reset button once. If the boiler has a summer/winter selector, move it to the reset position until the red LED turns off, then return it to winter position.

What sounds are normal from a Saunier Duval boiler?

Normal sounds include a gentle humming from the fan when the boiler is running, clicking sounds when the boiler ignites or switches between heating and hot water modes, and quiet water flow sounds. Concerning sounds that require professional attention include loud banging or kettling noises (which may indicate limescale buildup), persistent vibrating, grinding from the fan or pump, or any unusual rattling. If you hear concerning noises, switch off the boiler and contact a Gas Safe registered engineer.