Fault codes by maker
A fault code is the boiler telling you which safety or running check has stopped it. Codes differ by maker and by model, so these entries list only what each maker's own user documents print, and say which documents were read.
- Reading a fault code
Boiler fault codes are not a shared language: a code means only what the user manual for that exact boiler says it means.
- Resetting a boiler
How to reset a boiler depends on the model: printed methods run from one brief press to a five-second hold or a quick turn of a knob.
- Worcester Bosch display codes
Worcester Bosch fault codes defined in the user manuals read are few: EA, 1017 and LoPr, plus some status displays on the Greenstar 24/28.
- Vaillant fault and status codes
Vaillant fault codes defined in the user manuals read are mainly F.22 (low water) and F.28 (no flame at ignition); N codes mean limited running, and S codes report status.
- Baxi, Main and Potterton codes
Baxi error codes depend on which guide covers your boiler, and even E133 means a frozen condensate pipe in one Baxi guide and a gas or flame fault in another.
- Ideal boiler codes
Ideal boiler fault codes here come from two older user guides: letter codes on the Logic Combi and plain-English messages on the Logic+.
- Glow-worm fault codes
Glow-worm fault codes defined in the user manuals read are mainly F.22, F.28 and F.83, with F1, F5 and F22 on the older Flexicom cx.
- Viessmann display codes
Viessmann fault codes are mostly not explained to users: the Vitodens manuals read show a fault number but tell you to note it for the contractor, and define only a few displays such as CL and E3.