Carbon Monoxide Alarm Going Off
Your carbon monoxide detector is sounding, indicating potentially dangerous CO levels in the home.
What Is Causing This?
- 1Gas appliance burning fuel incompletely due to poor ventilation
- 2Blocked flue or chimney preventing exhaust gases from escaping
- 3Faulty or ageing gas appliance producing CO
How Urgent Is This?
This needs prompt attention. Delaying could cause further damage, safety risks, or significantly higher repair costs.
What Needs to Be Done
Open all windows, leave the property, and call the National Gas Emergency line. A Gas Safe engineer will test all appliances, check flues, and repair or condemn any unsafe appliance.
How Much Will It Cost?
National average estimate
Labour: £85 – £200 | Materials: £30 – £178
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Prices are estimates based on typical UK rates. Actual costs depend on the specific issue, accessibility, and your location. All quotes from tradespeople on Tradesfolk are completely free.
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Ask a QuestionHow to Prevent This
Have all gas appliances serviced annually by a Gas Safe registered engineer. Test CO alarms monthly and replace every 5 to 7 years. Never block air vents.
Related Problems
A smell of gas (rotten eggs) inside the house, which could indicate a gas leak.
The boiler shows an error code, flashes a warning light, or simply will not ignite when heating or hot water is called for.
Smoke from the fire or stove blowing back into the room instead of going up the chimney.
Other Gas Engineer Problems
Loud banging, kettling, or rumbling sounds coming from the boiler, particularly when the heating or hot water comes on.
The boiler pilot light repeatedly extinguishes, meaning the boiler will not fire up for heating or hot water.
A smell of gas (rotten eggs) inside the house, which could indicate a gas leak.
The boiler pressure gauge keeps falling below 1 bar, causing the boiler to lock out or lose heating efficiency.