Dehumidifier - water volume

I've been getting a lot of condensation on my windows in weather with outside temps under 8 degrees Celsius. I was pretty sure the house was dry and put it down to not opening the trickle vents often enough, steam from cooking and showers.
The glazing in the house is quite large and I have been venting the house quite often. I now have a dehumidifier (large one from a tool hire company) in my house a day now and moving it about. I'm getting about 500ml an hour at most and the unit is quite large. The house is open plan. Is this normal? Any ideas experience appreciated.

does sound rather a lot 12 litres a day, what is the extraction rate of the dehumidifer.

Ive had one going for a while with a measured rate of 10 lires per 24hrs and that only pulled about 2L per day, so either a high performence dehu or ur air is sopping. Either way leave it go and dry it out then once source is cured tis all done anyway.