Saunier Duval Appliance Repair in St David's

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 does error F7 mean on a Saunier Duval Condens boiler?

Error F7 on a Saunier Duval Condens boiler indicates a domestic hot water thermistor fault. The DHW temperature sensor is faulty or not properly attached. Switch off the boiler and contact a qualified heating engineer to inspect the sensor.

What does error F10 mean on a Saunier Duval Condens boiler?

Error F10 on a Saunier Duval Condens boiler indicates a central heating return thermistor fault. The return temperature sensor or cable is defective. Switch off the boiler and contact a qualified heating engineer to inspect and replace the thermistor.

What does error code 16 mean on a Saunier Duval Themaclassic boiler?

Error 16 on a Saunier Duval Themaclassic boiler indicates a gas safety valve failure. 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 F16 mean on a Saunier Duval Condens boiler?

Error F16 on a Saunier Duval Condens boiler indicates a flame detection fault - the boiler has detected a flame for more than 5 seconds after the burner stopped. 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 as the gas valve may be defective.

How do I bleed radiators when I have a Saunier Duval boiler?

Switch off the boiler and allow the system to cool. Check the boiler pressure is between 1 and 1.5 bar. Starting with the radiator nearest the boiler, use a radiator key to open the bleed valve until you hear air escaping. Close the valve as soon as water begins to flow. Repeat for each radiator in your home. After bleeding all radiators, check the boiler pressure gauge and repressurise if necessary.

What should I do if my Saunier Duval boiler shows 2.7bar?

The 2.7bar display indicates that water pressure has exceeded the safe operating limit. Excessive pressure can damage boiler components and may cause the pressure relief valve to discharge water. You may need to release some water from the system via a radiator bleed valve to reduce pressure.

Why does my Saunier Duval boiler provide heating but no hot water?

If your boiler provides heating but not hot water, the most likely cause is a faulty diverter valve (also called a 3-way valve). This valve directs hot water either to the radiators or to the hot water outlet, and when it fails it may become stuck in the heating position. Other possible causes include a faulty hot water temperature sensor or a problem with the boiler controls. Contact a Gas Safe registered engineer to diagnose and repair the issue.

Should I leave my Saunier Duval boiler on all the time?

Modern condensing boilers like those from Saunier Duval are designed to be efficient when running on demand. Using a room thermostat and programmer to control when heating is on is generally more efficient than leaving the boiler running continuously. However, the boiler should remain powered on (even in summer) so that frost protection can activate if needed.

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.