Please take a look at the boiler fault codes below. Don’t worry if you have one of these, it doesn’t necessarily mean your boiler is broken. Your boiler may just need resetting or you have an issue that is easily resolved.
Below we have the fault codes for the ecoTEC Plus series of boilers. You may have different fault codes as they differ across Vaillant boiler models.
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
More fault codes will follow soon.










