I defrosted an upright freezer by manouvreing it to the back door and using the hose on it...........fully defrosted in 20 minutes. And it still worked ok afterwards.
i know it would not be recommended and you do need to be very careful - electricity and water are not good together of course, but I do normally switch off and then give the bad areas a bit of a blast with the hairdryer and also use the bowl with hot water. Normally done very quickly ready to be switched back on.