Carbon monoxide alarm sounding
Treat a carbon-monoxide alarm as a safety event: move to fresh air, avoid using suspected fuel-burning appliances and follow the alarm/emergency guidance.
What to do first
- Prioritise people and immediate safety before diagnosis.
- Do not keep testing an unsafe system just to identify the fault.
- Use the relevant emergency/qualified professional route when there is immediate danger.
What could be behind it
- Alarm detecting a hazard
- Alarm/device fault or end-of-life
- Fuel-burning/electrical source requiring inspection
These are common possibilities, not a diagnosis of your specific home.
When to stop doing it yourself
Stop if you are unsure of the cause, cannot isolate the system safely, need to open fixed electrical/gas equipment, work at height, disturb hidden building fabric, or the problem is getting worse.
QUOTE CHECK
Typical quote components
- Safety assessment
- Appliance inspection
- Repair if required
- VAT
PARTS / TOOLS
Possible items involved
Do not buy parts until the cause is confirmed.
How to describe it to a professional
The carbon monoxide alarm is sounding.
NEXT STEP
Move from symptom to action.
Compare the right service, understand the quote and keep the completed work in My Home.