Built for gas engineers, trainees and training use. Not a DIY homeowner repair guide.
Who is using this tool today?
Built for professional and training use. Designed to support structured fault-finding, not replace manufacturer instructions, live testing procedures, or engineer judgement.
How do you want to start?
Use a fault code if you have one. If not, start with what the boiler is doing.
Beta version — built for real-world engineer feedback and ongoing expansion.
What manufacturer are you working on?
Which range/model is it?
What fault code is showing?
Choose the closest match and work through the checks one step at a time.
What is the boiler doing?
Choose the closest behaviour. This will route you into a sensible first check.
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