We have holding plate systems (one for fridge and one for freezer) which requires a quick defrost as turning off the unit would take too long. Fortunately we can relocate some frozen
food to our fridge at the cold plate while we defrost the freezer.
We use 2
remote temperature gauges that I
monitor daily without opening the lids, to see if temps are climbing.
At first , we directed a couple of pots of room temperature
water over the cold plate trying to get both sides. Problem was that although we could remove the heavy frost, the remaining film of
water would freeze on the plate, plus the water would freeze at the floor of the freezer or fridge. This turned out to be a short term solution and the thick frost returned quickly.
Then I thought to try a de-ice solution, like we do at airports. I purchased some
plumbing antifreeze (non toxic -50 C) from the local
hardware, the same we use in our water lines in the
winter. I filled a spray bottle with 100% pink
antifreeze. Now, following the pots of water, we dry the plate quickly as much as we can, and I spray the plate with the antifreeze, unable to reach the back of the plate of course. I then dry the plate as much as I can which then is frost free. Our plate remained frost free for about 3 days before beginning and the frost built at a slower rate as the antifreeze removed the water from the floor too. Temps dropped by over 4 degrees. The odour of the antifreeze spray dispelled quickly, it also had no affect upon our
food. Our food was returned to the freezer shortly after we completed the de-ice task.
Hope this helps.