I started this thread back in April, and there has been progress! And some camping
This camper, our 4th, was new to us this spring.
* All bulbs in the cabin and galley have been replaced by LED, with roughly 1/10th the power consumption of conventional bulbs.
* Purchased a Yeti 35L cooler, it’s about right for a couple days, gets a little small after that. But it does work well. No power required.
* Have barely used the vent fan, and haven’t used the furnace at all. Summer in the NW!
* Have used the sink/water pump a fair amount, more than expected. I’d never had one that worked as well as this, it’s pretty handy.
* I have 10 nights in the CI, running CPAP off the house battery. I’ve not done more than 2 nights before some level of recharging by driving the TV. It draws down significantly in two nights. I might get a third night out of it, or maybe not. Note that this is the original 76ah battery in a 2012, and seems to have a little reduced capacity, I’ll probably replace it for 2019. Possibly with the Victron 100ah Super Cycle, which is a half-inch taller than the cleat at the back of the battery compartment - needs more measuring and figuring!
* I have 1 night running CPAP off a new, dedicated battery (it arrived last week, finally!).
Learning continued along the way, and continues still.
The new batt is small enough for the headboard cabinet in a 550, along with -either- its charger or the CPAP. It’s a 60ah Victron Super Cycle AGM, of a new design that can survive being drawn down to 100% DoD (depth of discharge, about 11.89v, but tested down to 10.8v). As I understand amp hour (ah) ratings, a conventional 60ah AGM would deliver about 30ah to 50% DoD as a general target. In theory, and as tested by Victron, I should be able to get 60ah out of it when needed, but a charge should be completed quickly after that.
(Which means that the conventional 76ah AGM in the CI would deliver about 38ah with good longevity.)
These Super Cycle AGMs are in short supply; I had to wait 6 weeks. I purchased a Victron charger at the same time. Recommended is that chargers’ capacity should be about ah/5, so, for 60ah a 12amp charger. I purchased a Victron Blue Smart 12v/10a charger, biggest I’ve owned, I can check the stage of charge cycle via bluetooth from a smartphone.
That batt & charger ran about $290 with free shipping from Jamestown Distributors. This was a special order; the batt and charger don’t appear on their website. Yes, the Victron line is oriented towards marine use.
Per theory, I’m using about 6.8ah/night on my CPAP, or about 34 per 5 night off-grid trip. That would seem to give me a significant margin, but with only 1 night out since I got the new rig, I don’t have enough experience to validate that. That’s the design goal, hope it works out that way! I really should do some serious monitoring,
as Rotus8 recently posted. Another winter project!
Thanks for all the comments along the way - posters to this thread really helped me consider possibilities I’d not looked at before. Starting this, I was pretty sure I’d never want to deal with a second battery; that there was a new batt that should run 5 nights, with reserve capacity, that fits in the headboard cabinet and was affordable made all the difference!
P.S. It *really* helps to have a CPAP that accepts a 12v supply natively. Campers, you must request this whenever you’re up for a new device!
