Comma do one of those systems too, do a search on here, plenty have used them. The issue appears to be if you use either aircon or normal cooling almost exclusively, the other side of the system tends to get a bit mouldy. So if you never use AC and then turn it on, it has mould in it which smells. You get the same if you use AC all the time and then switch it off. The cleaner stuff works for a while, but the smell will come back. Personally I just have the AC on all the time (as it switches the compressor on and off when needed) and just leave it at that. No smell, but then I dont ever turn it off. If I do then it does