What does your boiler
fault code mean?
Plain English answers for 1,623+ codes across all major UK boiler brands.
Free. No registration. No call-out required.
Popular boiler brands
Vaillant
263 codes · 9 models
Baxi
208 codes · 9 models
Worcester Bosch
204 codes · 7 models
Ferroli
112 codes · 5 models
Viessmann
103 codes · 17 models
Glow-worm
79 codes · 2 models
Potterton
79 codes · 3 models
Alpha
71 codes · 4 models
Keston
66 codes · 3 models
Ideal
63 codes · 6 models
Ariston
62 codes · 2 models
Grant
56 codes · 6 models
How it works
1
Find your brand
Select your boiler manufacturer from our list of 20+ UK brands.
2
Enter your code
Type the fault code shown on your boiler display.
3
Get plain English answers
Understand what it means, whether it's safe, and what to do next.
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