Our NTU has MagneTek series model 6345 and it shows 14.1 volts all the time. Previous owner said it boiled the battery when left on. I do not leave it on now, just plug it in every 3 days. Will order from Randy one of following
Called Randy and he said a PD4645 converter. Upgrade.
I also see the PowerMax PM4B-60 (60 Amp 4-Stage Converter/Charger)
The powermax has a little higher charging voltage, but is not the upgrade. I have plenty of room, would it be better and easy to install