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Gas Appliance Condemned Or Capped Off
An engineer has attached a warning notice and turned your boiler, fire or cooker off — here is what that classification means.
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What's happening?
When a Gas Safe registered engineer finds a defect, they classify it under the gas industry's unsafe situations procedure and give you a warning notice to sign. There are two classifications that stop an appliance being used. Immediately Dangerous means the appliance is a danger to life or property right now, and it will be disconnected or capped on the spot with your permission. At Risk means one or more recognised defects exist that could become dangerous, and the appliance is turned off and labelled until they are put right. A third label, Not to Current Standards, records something that would not be installed that way today but is not unsafe — that one does not stop you using the appliance. Refusing permission to disconnect does not make the appliance safe; the engineer must then report an Immediately Dangerous situation to the emergency service.
What usually causes it?
- A failed flue integrity or spillage test on an open-flued fire, back boiler or water heater
- Combustion readings outside the permitted CO or CO/CO2 limits at the flue
- Insufficient or blocked purpose-provided ventilation for the appliance's gas rate
- A gas escape found on the installation during a tightness test
- A flue in a concealed void with no inspection hatch, so it cannot be proved sound
- A missing or defective flame supervision device on an appliance that requires one
- An unauthorised alteration to pipework, a flue or an appliance by someone not registered
Is it dangerous?
Immediately Dangerous means yes, right now — do not reconnect it, do not use it, and do not remove the label. At Risk means the appliance has defects that make continued use unwise until they are corrected. In either case the notice sets out what was found; keep it, because the next engineer will want to read it and, in rented property, it is evidence about the landlord's duty. Reconnecting a capped appliance yourself is both dangerous and unlawful, since work on gas fittings may only be done by a registered person.
Can I fix it myself?
Nothing on the appliance. What you can do is practical: read the notice and note the exact defects listed, arrange temporary heating or cooking, and if the property is rented send the notice to your landlord or letting agent straight away, because the landlord carries the annual safety-check duty under regulation 36. If you disagree with the classification you can get a second opinion from another Gas Safe registered engineer or raise it with the registration body — but leave the appliance off while you do.
When should you call a gas engineer?
Get a Gas Safe registered engineer booked for the repair as soon as you have the notice, giving them the defects listed so they can bring the right parts. Where the defect is a flue in a void, a chimney or ventilation, expect the fix to be building work as much as gas work. If the appliance is old, ask for the repair cost against replacement before ordering parts — the classification often reflects an appliance at the end of its life rather than a single failed component.
What will the gas engineer actually do?
- Read the previous warning notice and re-test the appliance against the same criteria
- Repair or replace the defective component, flue section, or ventilation provision
- Fit an inspection hatch or an approved alternative where a flue runs through a void
- Re-test combustion, flue flow and spillage and record the readings
- Remove the warning label and recommission the appliance only once it passes
- Issue documentation of the remedial work, and a landlord gas safety record where relevant
What the three classifications mean
- Immediately Dangerous — a danger to life or property now. Disconnected or capped with your permission; reported to the emergency service if you refuse.
- At Risk — one or more recognised defects that could become dangerous. Turned off and labelled until corrected.
- Not to Current Standards — would not be installed that way today, but is not unsafe. Recorded for information; you may keep using the appliance.
Frequently asked questions
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