CP12 Failed? What a Failed Gas Safety Check Means for Landlords
If a gas appliance fails its safety inspection, here's what it means, your legal position, and how Gas First puts it right fast across East London. Gas Safe registered (587401). Call 07927 882561.
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Upfront cost — no obligation A Landlord Gas Safety Certificate (CP12) records the annual gas safety check the law requires on the appliances you provide as a landlord. If an appliance is found to be unsafe during that check, it does not simply ‘fail’ quietly — the engineer must classify the fault, may need to make the appliance safe, and you as the landlord have clear legal duties to act. This page explains why properties fail, what happens next, and how we help you become compliant again quickly.
Why does a property fail a gas safety check?
Common reasons include an appliance that is leaking gas, poor combustion producing carbon monoxide, inadequate ventilation or air supply, a blocked or damaged flue, incorrect installation, or an appliance that is simply too old or worn to operate safely. The check covers the gas appliances, fittings and flues you provide as landlord, so a fault in any of these can mean a fail.
Common reasons include an appliance that is leaking gas, poor combustion producing carbon monoxide, inadequate ventilation or air supply, a blocked or…
What the safety classifications mean (ID, AR, NCS)
Unsafe appliances are classified under the Gas Industry Unsafe Situations Procedure. ‘Immediately Dangerous’ (ID) means the appliance is an immediate risk and, with your permission, will be turned off and labelled. ‘At Risk’ (AR) means there is a potential danger and it should not be used until fixed. ‘Not to Current Standards’ (NCS) means it does not meet today’s standards but is not immediately dangerous. The engineer explains exactly what was found and what is needed to put it right.
Unsafe appliances are classified under the Gas Industry Unsafe Situations Procedure.
What happens next — and your legal position
If an appliance is ID or AR, the engineer will, with your consent, disconnect or cap it and issue a warning notice; certain situations are also reportable to the gas authorities. As a landlord you cannot let, or continue to let, a property rely on an unsafe gas appliance — the legal duty to keep gas appliances safe sits with you. Once the fault is repaired and the appliance passes a re-check, we issue your CP12 so you are compliant again.
If an appliance is ID or AR, the engineer will, with your consent, disconnect or cap it and issue a warning notice; certain situations are also reportable…
How Gas First puts a failed CP12 right, fast
Because we carry out both inspections and repairs, we can usually diagnose the fault, quote you upfront, carry out the repair (or advise on replacement if the appliance is beyond economic repair), and re-issue your CP12 — often without a second company or a long wait. Working from our Bow and Dagenham bases we cover landlords across East London and Essex, and can set up annual renewal reminders so you never fall out of compliance again.
Because we carry out both inspections and repairs, we can usually diagnose the fault, quote you upfront, carry out the repair (or advise on replacement if…
Frequently Asked Questions
What happens if my rental property fails the gas safety check?
The engineer classifies the unsafe appliance (Immediately Dangerous or At Risk), and with your permission makes it safe and issues a warning notice. You must have the fault repaired and the appliance re-checked before it can be used, and you cannot rely on an unsafe appliance in a let property.
Can I still rent out my property if the CP12 failed?
You must not let a property rely on a gas appliance that has been deemed unsafe. Once the fault is repaired and the appliance passes a re-inspection, we issue a valid CP12 and you are compliant.
Who is responsible if a gas appliance fails — me or the tenant?
The legal duty to keep the gas appliances, fittings and flues you provide safe sits with the landlord, not the tenant.
How quickly can you repair and re-issue the certificate?
In many cases we can diagnose, quote, repair and re-issue the CP12 in a short timeframe because we handle both the inspection and the repair. We confirm the cost before any work.
What does it cost to fix a failed CP12?
It depends entirely on the fault — from a minor repair to replacing an appliance. We diagnose, explain the options and confirm the price upfront, with no obligation.
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