I'm very stressed.... Last night my CO detector went off intermittently for an hour. I replaced the batteries and it continued. I called the emergency number and whilst I waited for them to arrive my smoke alarm made some beeps as well. It's mains connected and about 6ft from the boiler (definitely NOT battery related). The emergency people came and shut off the gas etc but didn't pick up monoxide on their detector. However, an engineer has been today and has said we need a new sump. All good.
However, even though the boiler has been switched off, my monoxide detector has sounded once, closely followed by the smoke detector. I don't understand?!
Engineer is back later but I'm not sure why they are not picking up any leaks at all.