Originally Posted by Zeta
It would attach to your coach batteries, so when the relay closes at 13.5 V it will turn on the fans . This will happen only when the batteries are charging. So it's not exactly a key on 12v, but when the batteries are being charged either by the alternator or the converter.
I love this idea.........trying to figure out if I can somehow do this with my existing setup, which is:
blue sea bi-directional 7610 battery separator between starting and house batts
Solar panel/controller on house batts.
Sounds like I would need another controller like Zeta posted above........
This idea would have the muffin fan running whenever the batts are charging, either from solar or alternator-Brilliant!