You may want to check your fan tension pulley, after taking mine off, it was on it's way to failing. Just loosen the belt, or if your aux air is leaking it will already be flopping around, then spin the pulley and listen for noise. Prevost has a new bearing for about 35.00 that has to be pressed in and out or they have an upgraded pulley assembley for 160.00 that is suppose to be a new long life design.

I installed a 24V charger by Battery Tender for the chassis batteries, hard wired it to the batteries and used the 120V block heater plug in the engine compartment for power so I can turn it on/off with the breaker in the bedroom. This charger is a 3 stage, Bulk-Absorbtion-Float and will not cook the batteries. The price was 78.00 at Aircraft Spruce and it's weather proof.