That is the system that I replaced in our coach. We replaced it on the advice of Mike Canter because of the problem he had with that system.
It looks as though maybe a previous owner had a failure of that unit and just removed it instead of replacing it with something else.
I think it would be a good idea to get something there to protect your engine.
Previous Ride = 2000 Monaco Signature
New Ride = 2019 Pleasure Way Lexor FL.