We have just had a new boiler fitted and the installer put in a new CO detector. It is on the ceiling. I think CO is lighter than air but not 100% sure… Anybody got the answer?

Carbon monoxide is lighter than air. Co detector should be on the ceiling.

Not sure but ours is above the boiler and has worked on several occasions. Possibly scarier than the smoke alarm.

C0 mixes with air, so knee height if in a sleeping area or up to chest height- according to google

It is very slightly lighter than air, but assuming it is coming from a boiler then it is probably “warm” so would tend to rise too.

Carbon monoxide is lighter than air

It’s not that much lighter. CO has a mol wt of 28 amu and air is 29 so I’d call it neutrally bouyant.

When I looked into it before it seemed having a combination of ceiling mounted and between chest and head height was recommended.

Wot gonefishin said. Put it somewhere you’ll hear it if it goes off.

The instructions that came with mine suggested head height, so as above – bed level height in a bedroom, sofa back level in a living room etc.

Not sure but ours is above the boiler and has worked on several occasions. Possibly scarier than the smoke alarm.

? we were told not to put it near the boiler?