Good overview of lithium batteries and a solar/lithium upgrade on a larger RV

[mojoman]

The are around 5000 BTU, 30- 46 amps 12v. Just ran my Coleman 13500 on my inverter again, it pulled 130 amps 12v. They are little more efficient but you will need at least two units in the summer.

[gregmchugh]

The Onan that uses 2 lb of propane at 2000 watts load is the smaller propane fueled 2500 not the larger 3600. Would be interesting to know lb/hr on the converted Honda/Yamaha models at full load. Can they handle the same load on propane that they do on gasoline?

There are various 12v air conditioner options from the smaller semi truck cab air conditioners up to larger ones. Roadtrek offers an underfloor 12v system that provides the same cooling capability as their 120v roof units but with more energy efficiency. I have not seen actual BTU and amp load numbers though for the underfloor system.

[avanti]

I am actively shopping for a 12VDC split A/C system for under-the-van mounting. There are a bewildering array of options. My current favorite is this one:

Stationary air conditioners for trucks - SW ARCTIC PLUS

It has dual Danfoss compressors, so it can run "low" or "high" very nicely.

Does anybody know what unit RT is installing? I would greatly appreciate any advice anybody has to offer on this topic. A quiet, DC-powered unit that is not on the roof would be da bomb. I am looking forward to turning the big hole in my roof into a kickass skylight.

[gregmchugh]

I recently saw an under side picture of a Roadtrek Sprinter XL showing the AC. The label was Frigiking and I had heard before that it was a custom unit from ProAir and the label aligns with that...

ProAir

[wincrasher]

Mid-American (now Chinook?) was showing a 12v air conditioning system in their van at Hershey last year. Actually is was two systems working in tandam - the cab air system and one in the back. Required engine idling though. I assumed that this comes from the limo side of their business, as it appeared as something you'd have in an airport limo or shuttle. They claimed 56,000 btu of cooling. That was the only thing I liked about their product, the rest was way too garish for my tastes.

As far as ARV going with the Delco alternator, I'm told that they wanted to go with it earlier, but it was too costly. They got better pricing on it now somehow. Additionally, the Nations Alternator runs hotter than they'd like to see - even with their (ARV's) tremendous cooling system. Avanti, have you measured how hot your's gets? Supposedly when they get too hot, the amperage drops off.

[gregmchugh]

Someone who understands the details can explain it but I think the 56,000 BTU value is somehow measured differently than the BTU value specified for typical RV roof AC units. My understanding is that the Roadtrek underfloor AC is something like 35,000 - 40,000 BTU but provides equivelent cooling to the standard 11,000 BTU Dometic roof AC.

[avanti]

Originally Posted by wincrasher

Mid-American (now Chinook?) was showing a 12v air conditioning system in their van at Hershey last year. Actually is was two systems working in tandam - the cab air system and one in the back. Required engine idling though.

Sounds like it has an engine-powered compressor. I am looking for a 12VDC compressor unit.

As far as ARV going with the Delco alternator, I'm told that they wanted to go with it earlier, but it was too costly.

Too costly? What is cost to an ARV customer?

Additionally, the Nations Alternator runs hotter than they'd like to see - even with their (ARV's) tremendous cooling system. Avanti, have you measured how hot your's gets? Supposedly when they get too hot, the amperage drops off.

No. I suppose I could. But, I guess I am pretty confident that the Balmar regulator with its alternator thermistor does the right thing and keeps the alternator cool. The ARV fancy cooling system is pretty pointless. It is true that the Balmar modulation reduces output briefly (I can watch it doing it on my battery monitor), but the available capacity greatly exceeds my practical requirements, so who cares? I just can't imagine wanting more amps. I suppose it may be true that running a large AC while driving might not break even, but (a) that would require an unreasonably large A/C (my Dometic draws 103 amps including inverter losses--actually measured. That is over 1200 watts); and (b) as I said before, I have never found my dash A/C to be inadequate. The whole proposition just seems like overkill to me.

[gregmchugh]

Avanti, I assume you saw the info you asked for on the source for the Roadtrek underfloor DC air conditioner? You are welcome...

[avanti]

Originally Posted by gregmchugh

Avanti, I assume you saw the info you asked for on the source for the Roadtrek underfloor DC air conditioner? You are welcome...

Yes. Thank you. Frigiking does seem to be one of the brands that ProAir sells under. This whole market is very confusing, with all the rebranding that goes on.

[gregmchugh]

Here is the picture if the underside of a Roadtrek XL Sprinter with the AC compressor and condenser and Ecotreks...

http://www.classbforum.com/forums/me...icture427.html

[Reed]

Sheral

Just talked with son (we are visiting younger son in Fort Collins and older son is in Sange de Cristos above Las Vegas, New Mexico). He will be installing two Blue Sky MPPTs, one for the 315 W and the other for the 100 W panels. Turned out that the Manzanita Micros LFPs were by far the least expensive. They are designed for EV usage. Their CALB batteries are usually sold packaged in an aluminum and polycarbonate case. Manzanita is temporarily out of CALB batteries and cases, except for two cases that were demonstrators. So they are shipping the demonstrator cases and the battery cells will be shipped from the CALB distributorship in California.
Reed and Elaine

[Reed]

What happens to A/C and associated paraphernalia (Roadtrek XL) on muddy or gravely roads? We plan to do the Trans Labrador this summer which has 500 km of gravel road.
Reed and Elaine

[gregmchugh]

Originally Posted by Reed

What happens to A/C and associated paraphernalia (Roadtrek XL) on muddy or gravely roads? We plan to do the Trans Labrador this summer which has 500 km of gravel road.
Reed and Elaine

Good question. Not sure if there is an opening on the front of that AC compressor or not. The AC condenser looks like it could get mucked up. The Ecotrek modules are sealed boxes so probably not an issue with those.

[Reed]

gregmchugh

The picture of the undercarriage of that Roadtrek had some large openings in the A/C. We have gone down a number of very muddy roads (as to our son's place in the Sangre de Cristos in northern NM) where we can wind up with several inches of mud on the undercarriage. Our fifth wheel can look like a frosted chocolate cake on the lower portions.

Davydd was worried about heating of the LFP inside the vehicle. We have been monitoring our LFP (9 kW-hrs basically) for over three years (wife thinks I am OCD, been that way since RVN) and have not noted much heating above ambient. There is heating if inverter and batteries are in same enclosed box (as noted earlier in reference to Chris Dunphy's blog). This has been no problem with a 5th wheel since we have the battery bank in the front bay and we can get very good cross ventilation there. Have 12 V receptacles in the bay for 30 W lamps for heating bay or 12 V fans (12 W) for additional cooling. The Manzanita Micro cases do have fans to maintain ventilation.

However, son plans to utilize an opening to undercarriage to get cool air into the battery area under rear bed. Will use a small 12 V fan. That combined with a larger 12 V fan at the baggage door under the bed (now to the battery bank) or the Fantastic Fan should draw enough cooler air to keep the batteries cool.
Reed and Elaine

[avanti]

I am planning on feeling my way wrt protecting the condenser. Once I have chosen an actual unit, I will assess the risk. I certainly could imagine encasing it in a protective case, possibly with an actuator-operated vent/cover.

I don't think there will be issues with the compressors--they are pretty sealed. There may be some electronics that need protection, but they don't require much ventilation.

[gregmchugh]

Originally Posted by avanti

I am planning on feeling my way wrt protecting the condenser. Once I have chosen an actual unit, I will assess the risk. I certainly could imagine encasing it in a protective case, possibly with an actuator-operated vent/cover.

I don't think there will be issues with the compressors--they are pretty sealed. There may be some electronics that need protection, but they don't require much ventilation.

Any idea if that compressor box under the Roadtrek has an air opening on the front end where it would get a lot of gravel and mud thrown up from the rear tires?

[wincrasher]

Originally Posted by avanti

Sounds like it has an engine-powered compressor. I am looking for a 12VDC compressor unit.


Too costly? What is cost to an ARV customer?


No. I suppose I could. But, I guess I am pretty confident that the Balmar regulator with its alternator thermistor does the right thing and keeps the alternator cool. The ARV fancy cooling system is pretty pointless. It is true that the Balmar modulation reduces output briefly (I can watch it doing it on my battery monitor), but the available capacity greatly exceeds my practical requirements, so who cares? I just can't imagine wanting more amps. I suppose it may be true that running a large AC while driving might not break even, but (a) that would require an unreasonably large A/C (my Dometic draws 103 amps including inverter losses--actually measured. That is over 1200 watts); and (b) as I said before, I have never found my dash A/C to be inadequate. The whole proposition just seems like overkill to me.

Well, I imagine the whole point to most customers for these type systems is running air conditioning. Either off the alternator or the battery packs. I guess the fear is running the AC and it outstripping the charging ability of the 2nd alternator. Sounds like it is a real possibility in the 100-120 amp range, with the drop off anticipated.

[mojoman]

Has anyone used a thermal imaging camera on their RV? I've been investing much effort in insulation and eliminating as many thermal bridges I can. I hope the reward will be not having the AC or heater cycle as often. The headliner in most rigs is an easy improvement as most MFG's install limited or no insulation.

[gregmchugh]

Thermal imaging camera...

Assessing the Insulation in our RV with an IR Camera

[Reed]

How does on heat the vehicle when it is all electric i.e., no propane aboard? Running the engine heater seems like a waste of engine hours as well as fuel.
Reed and Elaine