Been using the hot & cool formaldehyde for months, daily with no issues but out of nowhere it started emitting a chemical like odour. Similar to the smell of permanent marker ink. I didn't pick up where it was coming from for a day or so but determined its definitely from the machine after having it off for a period. My filter is still at least 90% but has it taken in something unusual and been compromised? I don't use chemicals around the machine, the only thing I can think of is maybe some spray hand sanitiser being used in an adjacent room which causes the VOC to rise as I walk past. It doesn't smell spoiled or rancid in any way, but is headache inducing. I've stopped using immediately on realising the issue.
(Edited by moderator – Tags added and moved to ‘Air quality’ forum)