I haven’t tried a large sample, but I’ve tried 2 ionic air purifiers (both release negative ions, but one can be equipped to not give them off) and a couple of HEPA filter purifiers.
I can’t sleep through the night with the ionic ones. I keep waking up in the middle of the night. I don’t get this problem with the HEPA ones.
It isn’t the noise, because a fan doesn’t wake me up, neither do the HEPA purifiers turned on full blast (while one of the ionic purifiers is near silent).
The noise level may not be the problem, but the particular noise might be. In addition, your body may react to the increased negative ions in the air (I say ‘may’ because I have no idea if this ion stuff has any merit at all).
But I’d guess it’s all in your head. You either had some anxiety about the ionic purifiers to start with, or perhaps woke up coincidentally after installing them, and from then on you’ve been reinforcing the concept that they are responsible for waking you up.
Or they are possessed, always a possibility with modern technology.
If I run one a few hours before bed in the bedroom, then shut it off before bed I don’t get insomnia. This has happened several times, so I don’t think it is a coincidence.
I don’t think it is psychosomatic. I’ve had psychosomatic insomnia due to anxiety and this isn’t the same. My anxiety based insomnia is delayed sleep phase insomnia, not an inability to stay asleep and constantly waking up.