Which sealant for hoses on back of Zanker fridge/freezer model KSU 2800 ?

The unit started to overheat even after the door seals had both been replaced. I checked round the back and found that the sealant around the cold air hoses where they enter the fridge and freezer had perished and there was a ball of ice around each of them. What type of sealant do I need to put around the hoses? Will one of the household silicone types be OK?

Adam
July 2007