[microtonal]

I have HA send me a notification to ventilate my office when the air reaches 1000ppm CO2. The IKEA ALPSTUGA is often off by 300ppm even under 1000ppm. If I'd use it, I'd be getting notifications at 700ppm.

It is a thermal conductivity sensor, which is a very indirect way of measuring CO2 and is very sensitive to environment factors. You only get somewhat good readings in lab conditions.

Don't by the ALPSTUGA for anything but very rough trends, there are much better affordable options.

[Gigachad]

Within 300 ppm is more than good enough. Realistically 1000 ppm is not that bad. The average meeting room is multiples of that.

Also in my experience it’s much more accurate than that.

[microtonal]

I notice that thinking becomes less clear when going above 1000ppm, so I let HA send a notification at 1000ppm. With ALPSTUGA it would send already at 700ppm. By the way, above 1000 the divergences become even larger due to the inaccuracy also being 10% of the ambient CO2 concentration (in optimal circumstances, probably larger IRL). So, suppose you want to be notified at 2000 ppm, the IKEA sensor might already do so at 1500 or 1600 ppm and it continuously drifts, so it's not like you can use a particular offset.

Besides that, what's the point? There are much better meters in a similar price class. As an additional benefit, they can last months or up to a year on two AA batteries.

ALPSTUGA is an inferior product.

[Scroll_Swe]

>With ALPSTUGA it would send already at 700ppm.

"oh no I am getting too much fresh air"

I get your point but come on.

[microtonal]

In some situations it means opening a windows, with big temperature drops when it is cold outside.

At any rate, this is really a weird discussion, because you can get far more accurate meters at similar price points. Why waste your money on a much worse meter?

[Scroll_Swe]

The IKEA one looks cuter :3

[summm]

Can you recommend some?

[microtonal]

Mentioned two here: https://news.ycombinator.com/item?id=48783879