fridge problem?

Hello everyone, I am new to caravanning and have a 2006 Ace Award with what I believe is a pretty standard 3 way fridge. I have tried the fridge whilst hooked up to the mains supply on a CL recently. The indicator light comes on  as if the fridge is working properly, but it does not get very cold, certainly not cold enough to freeze the ice cubes for my G and T, or indeed to keep ice cubes frozen. Looking inside the fridge, there is a label suggesting that if the fridge is not getting cold enough, change to gas operation. I've done this and the fridge works fine. Is this likely to be a problem with the fridge? or the supply on that particular CL ?  Thanks again, Mick Rumble