1972 Revcon
Old Magtek converter
A diode is not going to do what you want
Either get a different battery
Or
Install a different converter
Even then you have to deal with the alternator voltage ,
Unless you disconnect the house from the alternator/isolator/combiner
And have no charging to the gel battery while engine is running
Are you sure it says GEL on the battery
And not Sealed AGM ?
Many people come on here calling any sealed battery Gel
AGM does not require any special treatment, other than a slightly higher max charging voltage,
Much better suited to RV use than Gel
