Unfortunately it does seem like this ITS-30R transfer switch may be discontinued. Calling the manufacturer is a good idea as they may come through with a timer control board for you at least (or reduced cost complete unit). There are lots of equivalent transfer switches on the market, but of course either a repair or replacement is going to be an access pain for you by the sounds of things. Too bad you can’t remove the face frame of your complete drawer section to give full open access for the repair, but that might cause more damage. I wonder how any RV repair tech would repair/replace it if access is so bad? Good luck.
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