Vaillant Boiler Error Codes
Vaillant boilers use a range of fault codes to highlight issues affecting performance. Common codes include F28, which indicates ignition failure, and F29, which signals a system pressure drop. Other codes, such as F75 and F80, point to issues with the fan or gas valve. Fault codes help identify problems such as blockages, sensor malfunctions, or low pressure, allowing for quick identification and resolution.
For more complex issues, like a faulty PCB or gas valve, it’s important to contact a qualified Vaillant engineer to ensure safety and proper repair so get in touch with AB Plumbing & Heatings engineers.
Interruption: Cylinder sensor: Only in conjunction with F.91NTC defective, NTC cable defective, defective plug connection on NTC, defective plug connection on the actoSTOR electronics
Safety switch-off: Low water pressure: No or insufficient water in the product, water pressure sensor defective,
Fault: Fan: Plug on fan not correctly plugged in, multiple plug on PCB not correctly plugged in, break in cable harness, fan blocked, Hall sensor defective, electronics defective










