Call Hotpoint and INSIST the defrost heater is moved to the bottom of the evaporator.
Hotpoint know about this problem yet refuse to acknowledge it publicly!
Martin Smith
September 2008
I take it that you have taken the plastic vents off the bottom and hooved the dust out? This improves the efficiency. The freezer compartment is cooled first, yours may have the oomph for that but not the freezer. Unplug, clean and turn back on again, then look into getting spares for it.