Why not look for a manual? It'd have been useful if you had given the make as well as the partial model number. There are at least three manufacturers I found with a fridge freezer (or frig if you must) that have the string "187B" in the model number. One is Hotpoint, one is Whirlpool and there's a weird Australian site mentioning Hoshizaki.
Here's a few links that may be useful.
You might also consider whether the "few years old" appliance was knackered when you got it.