Saunier Duval Repair Service in Ladybrook and Bull Farm

What does error F20 mean on a Saunier Duval Condens boiler?

Error F20 on a Saunier Duval Condens boiler indicates software incompatibility between components. This can occur after incorrect replacement parts are installed. Contact a qualified heating engineer to install compatible components.

What does error code 06 mean on a Saunier Duval Isofast boiler?

Error 06 on a Saunier Duval Isofast boiler indicates a central heating flow NTC sensor fault. The temperature sensor is faulty or disconnected. Switch off the boiler and contact a Gas Safe registered engineer.

What does error code 15 mean on a Saunier Duval Themaclassic boiler?

Error 15 on a Saunier Duval Themaclassic boiler indicates a gas mechanism fault. This is a serious gas safety issue. Do not use the boiler. Switch it off at the power supply immediately. If you smell gas, do not operate any switches, ventilate the area if safe to do so, leave the property and call the Gas Emergency Service from outside. Contact a Gas Safe registered engineer immediately.

What does error 0 & 8 (also shown as 08) mean on a Saunier Duval Ecosy boiler?

Error 0 & 8 on a Saunier Duval Ecosy boiler (display alternates between 0 and 8, also referred to as code 08) indicates an air pressure switch failure. This safety device ensures proper air flow for combustion. Switch off the boiler and contact a Gas Safe registered engineer.

What does error 2 & 8 (also shown as 28) mean on a Saunier Duval Ecosy boiler?

Error 2 & 8 on a Saunier Duval Ecosy boiler (display alternates between 2 and 8, also referred to as code 28) indicates the fan is stationary or not sending a speed signal. The fan may be blocked or faulty. Switch off the boiler and contact a Gas Safe registered engineer.

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.

What safety devices does a Saunier Duval boiler have?

Saunier Duval boilers include several safety devices: an overheat thermostat that automatically shuts down the boiler if temperatures become excessive, an air flow safety device that turns the boiler off if flue obstruction is detected, automatic shutdown during power failures (with automatic restart when power returns), and frost protection to prevent freezing in cold conditions.

What is the expansion vessel and why is it important?

The expansion vessel is a small tank inside your boiler that absorbs the increased water volume as the heating system heats up. Without a functioning expansion vessel, system pressure would rise dangerously high when hot and drop when cold. Signs of a faulty expansion vessel include pressure rising significantly when heating is on and dropping when cold, or the pressure relief valve discharging water. Expansion vessel maintenance should be part of the annual service by a qualified engineer.

Is my Saunier Duval boiler compatible with smart thermostats?

Many Saunier Duval boilers manufactured since 2012 are compatible with smart thermostats via the eBus communication protocol. The manufacturer offers dedicated smart controls that integrate directly with compatible boilers for optimal performance. If using a third-party smart thermostat, check compatibility with your specific boiler model. A qualified heating engineer can advise on the best options for your installation.

How do I repressurise my Saunier Duval boiler?

Before approaching the boiler, ensure there is no smell of gas. Locate the filling loop underneath your boiler - this is typically a flexible silver hose with two taps or valves. Ensure the boiler is switched off and has cooled down. Open both filling loop taps slowly to allow water into the system. Watch the pressure gauge and fill until it shows between 1 and 1.5 bar. Close both taps securely once the correct pressure is reached.