CO monitors

[andyoxon]

Gas boiler man said our carbon monoxide unit is 7yrso - so should be replaced.  LCD panel with ppm readout worth it?  Or just go for a basic one?

[De Sisti]

All depends on how much you're willing to spend.
https://www.argos.co.uk/product/7001590

[Greenbank]

Most with a digital readout don't show a figure if it's less than 30ppm (otherwise people start to panic if it's non-zero).

I recently got one for £25 from Sainsbury's, no digital readout. Says it is good for 10 years so £2.50/year isn't bad.

[ian]

Indeed, they're only accurate to a certain low ppm and they won't make claims below that, plus it would be unnecessarily worrying, all internal combustion processes will make some carbon monoxide. It's always worth testing the one you've bought – a smouldering match close to the detector will do.

Ours has a display, but I don't exactly check it often, and when I do, it says zero.

[andyoxon]

Thanks all.  Probably just get something basic - fireangel/kidde

[robgul]

Hmm - 7 years old and replace?   Ours is 20 years old and the British Gas boiler service man checked it and pronounced it OK - it's a basic Kidde one ... probably pu 2 or 3 batteries in it since new.     

I'll leave well alone as we (subject to the fat lady singing) sold the house today . . . 20 years to the day since we moved from the previous house.

Rob

[Kim]

The sensors use a chemical process with a limited shelf-life.  How limited depends on the type of sensor, but I'd expect 5-10 years.

Note that the test button is unlikely to test the efficacy of the chemical part of the sensor, just the electronics.  It's not like a smoke detector that can usefully be tested by fudging the bias points.

[ian]

Yes, replace these things, it's not worth taking a chance that it might still work, given that any demonstrable inefficiency may be terminal. As far as I know, pressing the test button just demonstrates that it can make a noise. A smouldering match should activate both smoke and CO detectors and demonstrate they're genuinely working.