Does anyone know about carbon monoxide ?

[FrancisSeaton]

So alarm went off yesterday , wasn't the co2 warning but the ventilate warning. So we opened windows doors etc and went outside. Called cadent who capped off the gas supply but didn't think there was a leak. The alarm went off again this morning but this time was the co2 alarm - however the gas supply was capped off at this point.
So a gas safe engineer came out checked the appliances did readings and no co2 detected. He then chucked the old monitor in the kitchen bin and installed a new one. This evening I hear a loud beeping and look across to the new one- nothing coming from there . Open the bin and it's coming from that alarm! I do over worry but am I okay to assume it was a faulty alarm? Or is it even possible to detect co2 when the gas is off and when the alarm is in the bin?

It's probably low on battery power so it's going off. That's what happens to the stand alone battery powered smoke alarms, even though they say battery life is 10 years. The fire brigade came out and fit new ones at my parents, the old ones were only 4 years into the ten year battery life

It sounds like a faulty alarm. Isn't carbon monoxide a by-product of fuel burning? So if there isn't any gas on and no woodburner or cinder ashes anywhere, I wouldn't have thought there would be a carbon monoxide presence. And if the new alarm wasn't going off?

It's a faulty alarm. Get it out of the house.

Your title is about carbon monoxide, and you have written about carbon dioxide? Which is it? There is a big difference

I assume this is just a typo type thing but CO2 is carbon dioxide?

I’d get another alarm and see if it happens again.

Doh!!! Sorry carbon MONOXIDE!
Maybe I've been overcome with fumes 🙈
It was a non replaceable battery detector

P.s. it's a CO alarm not a CO₂ alarm as monoxide means only 1 oxygen atom.

Probably a faulty alarm or battery running low.

It's CO

So you have one alarm going off, and one alarm not going off? Get a third alarm in and see what it does. They should not be fixed to anything, because you are supposed to take them with you if you evacuate, so you can make sure you are going far enough away. So in theory, you should just be able to ask a neighbour if you can borrow theirs for a few minutes?

Yeah the new one isn't going off

We had the same thing when the batteries were going in our alarm. If it has been checked, and the new alarm is not sounding then chances are it is fine

I just read all the conversation and I would like to say something on it.
It does sound like the old alarm was faulty, especially since it continued beeping even after being thrown in the bin with the gas supply capped off. The fact that a Gas Safe engineer found no carbon monoxide present and replaced the alarm confirms this. It’s very unlikely for a properly capped system to emit CO. You’re right to be cautious, but in this case, it seems like the alarm itself was the issue. Just make sure to test the new monitor regularly and keep good ventilation in place.

We had this with ours, took it to the garage at the end of the garden where there are no appliances or sources of CO and it still wouldn't stop beeping, we put it in the freezer in the end to muffle the sound till we could take it to the tip. They should be replaced after 10 years.

Sounds like a classic case of a worn-out or faulty unit! Once these detectors reach the end of their lifespan, they can definitely start acting up like that. Good call on isolating it to confirm there were no actual CO sources, better safe than sorry. Replacing after 10 years is spot on.

Just realised I forgot to mention something important in my previous comment, we were talking about Carbon Monoxide (CO) detectors. These devices are crucial for safety, especially as they can wear out over time and start giving false alarms.
If you are dealing with beeping CO alarms or want to understand how to properly test and maintain them, I’ve shared some helpful info here:
Carbon Monoxide Testing.
It covers why regular testing is essential, how CO can affect indoor air quality, and what to do if your detector starts acting up. Better safe than sorry when it comes to invisible dangers like CO!