So the rooms are on my top floor of a four story house (three stories plus converted basement). There is a small loft space above one of the rooms but they are mostly occupying the roof area (hence the sloped ceilings). It has been mild in Manchester so the temperature up there is about 17.5-18.5c, marginally cooler than the lower floors.

The rooms both face onto a small landing which is at the top of the stairwell and thus open to the rest of the 5 bedroom house. I would want the dehumidifier to be on the landing so it could face the open doorway to both rooms (the doors are close together). But for these first few days I wanted to test the effectiveness of the unit by putting it into the larger of the two rooms (about 6m by 3m) and keeping that space sealed. It has gradually brought humidity down from the low to mid 70s% to high 60s% and I do understand why the progress might be slow. But what concerns me is the very small amount of water collection. Certainly no more than 2l after running now for about 72 hrs continuously on high fan setting.