My caravan fridge Thetford smart energy selection will not work when gas is required, it only acts for some 5-10 seconds then cuts out. Two years ago we had a new board fitted in the van because of this failure, we have used the van once since then, this year with another service by another company the fridge is the same, just seconds then cuts out. He reccomends another new board. These are something like £180 each plus labour. Do you have a solution?