Coach battery shut off solenoid

burnt up 2 in 24 years?
about evenly spaced out?
Who told you they were burnt out?
Did you try repair? This involves disassembling the solenoid and burnishing the big brass washer inside so electric contact is reestablished.

The 6300 converter is a piece of dog sh*t!
I would get a lower section replacement, otherwise you will be boiling your batteries away. A new lower section solid state would help a lot.
I leave mine house batteries on, as the rig is operational at a moments notice. I have 6 volt golf cart batteries.
I doubt whether your battery disconnect relays were truly bad.

Many RVer's upgrade from the old Magnatec to a modern "smart charger" like a Progressive Dynamics 9245. A new converter won't cost that much and is a relatively easy DIY project (lots of examples on the net). Not sure why your battery disconnect are burning up - the Intelitec ones are protected by fuses.

No 2 in one year.

They were definitely bad. They had 12v on one side and noth8ng on the other with 12v and ground to little post. Replaced silenoid everything works again. Fyi....they can not be taken apart and cleaned.

If like this one it can be taken apart and cleaned/burnished

Applying 12 volts to small posts is not a good way to check. If it is like the posted photo, they are a latching relay. You apply momentary power to latch and then apply momentary reversed power to release.

I also had one go back on our four winds. I replaced with a simple battery dc. I also went to the intelli power lower unit on both the class c and the tt we are in now. AWESOME. If you end up shopping ebay or amazon for your new converter make sure they are an intelli power dealer, otherwise your product isn't supported by manufacturers.

Here is a good place to look for a replacement. Good support!
Best Converter