apm 6825 size and assorted queries.

hi all,
thanks for allowing me to post, my unit is a MFI APM 6825 and I wish to know what the capacity of it is, I have the manual but it does not state this.

second query, this unit is over 5 years old, and AS FAIK all the time we have had it the motor has run near on all the time, if it switches off its only about 4 or 5 times per day if we are lucky, freezer temp stays about 2 star according to my freezer thermometer which is stuck to the inside of the top shelf flap, the fridge, well this is where I would wish it to be better, I have waved my infrared temp gun about just now, and a 4 litre milk stood on the top shelf(for 3 days) registers 10c, a can of tuna at the back of the lower shelf shows 2c, and yoghurt in the bottom shows -1.5c.

on the face of this investigation it looks to me as though it working ok, which surprised me I must admit, so I ask, how does this sound, but more importantly is the motor on this model supposed to run for so long, the reason for this enquiry is that my wife has bats ears, and is always moaning about the motor always running

thanks for any replies
voith