Tiniest Hymer Promaster Carrado/Axion

[booster]

I just looked at the Axion site and it shows a base unit standard battery of 105ah of AGM battery. Getting to 600ah is going to require nearly 5 more of the same at about 65# apiece.

Properly set up, the UHG will work well with a large battery bank of AGMs. Several of us here do that currently with 440ah banks. The solar can be used to do the "top off" charge of the AGMs once the UHG does the major charging up to about 80% full. Of course, all of this stuff has to be setup well and work well together, and we don't know how well the Hymer stuff will do that. If you are not going to have more than about 220ah of AGM batteries, you will be able to charge them fine off the van alternator, again assuming things are setup right so you don't either overload the alternator or overheat the batteries.

Hymer probably has the solar going to the AGM in the lithium setups to make sure they always have enough power in it for dead lithium module revcovery, plus the solar normally needs to see a battery on it's output to regulate voltage properly. Not an ideal system by anyone's imagination.

200 watts of solar will keep up to a low power use camper with a compressor frig, in decent sun conditions. It would be marginal in poor sun or if you run any high load stuff like the microwave very much. Solar is nice, but IMO you need good alternator or generator charging to be available in case of poor sun or heavy use, especially if you need to recover quickly. There are many threads here on the forum on power use and management with all the different sources, with explanations of how to control and monitor it all.

IMO, the Voltstart is not worth the effort, especially if you are not trying to run air conditioning off batteries. With a decent battery monitor, you will know when you need to run the van so you can do it at appropriate times and places, without it choosing when it wants to start.

[BBQ]

Originally Posted by silex840

For some reason I thought it was the curb weight which includes all engine fluids and full gas tank. Although Carado lists it on the brochure as "loaded vehicle weight" which is what threw me off.

Engine fluids (oil, antifreeze, etc.,) are included, but not fuel.

Loaded... I guess it means all options? ie microwave and toilet?


The best way to find out your towing capacity is to weigh the vehicle.

[silex840]

Originally Posted by booster

I just looked at the Axion site and it shows a base unit standard battery of 105ah of AGM battery. Getting to 600ah is going to require nearly 5 more of the same at about 65# apiece.

Properly set up, the UHG will work well with a large battery bank of AGMs. Several of us here do that currently with 440ah banks. The solar can be used to do the "top off" charge of the AGMs once the UHG does the major charging up to about 80% full. Of course, all of this stuff has to be setup well and work well together, and we don't know how well the Hymer stuff will do that. If you are not going to have more than about 220ah of AGM batteries, you will be able to charge them fine off the van alternator, again assuming things are setup right so you don't either overload the alternator or overheat the batteries.

Hymer probably has the solar going to the AGM in the lithium setups to make sure they always have enough power in it for dead lithium module revcovery, plus the solar normally needs to see a battery on it's output to regulate voltage properly. Not an ideal system by anyone's imagination.

200 watts of solar will keep up to a low power use camper with a compressor frig, in decent sun conditions. It would be marginal in poor sun or if you run any high load stuff like the microwave very much. Solar is nice, but IMO you need good alternator or generator charging to be available in case of poor sun or heavy use, especially if you need to recover quickly. There are many threads here on the forum on power use and management with all the different sources, with explanations of how to control and monitor it all.

IMO, the Voltstart is not worth the effort, especially if you are not trying to run air conditioning off batteries. With a decent battery monitor, you will know when you need to run the van so you can do it at appropriate times and places, without it choosing when it wants to start.

Thanks for your input! And you're right!

Battery – 12V, 105 AH @ 20 hrs

I mentioned 600Ah, because others here have quoted the battery at 200Ah. Can someone who made that claim earlier in this thread chime in? If this is true I'd probably just get one more to get it to 210Ah to optimize the current setup on stock alternator. Then later in the future get higher capacity AGM or go to Lithiums and upgrade the panels to higher wattage that will fit in the same footprint. Plus go for the UG assuming it can be wired to work with AGM otherwise might have to default to Lithiums at that point.

[booster]

The 200ah is probably referring to a single lithium module.

[silex840]

Originally Posted by booster

The 200ah is probably referring to a single lithium module.

Great! You're probably right! Now I'm getting my AGM and Lithiums mixed up
Amp-hours is Amp-hours after all and I must have taken them out of context.

[kite_rider]

Silex, welcome to the Axion if you've actually bought one by now.

Per your question on the rope light control, the difference between the controllers is how you adjust the dimmer on the light. Mine has the circle style, you slide your finger around the circle to make it brighter or dimmer. The other controller just has a 'brighter' or 'dimmer' button.

For what it's worth; before I owned it I was all wrapped around the axle about battery capacity, lithium, UGH, etc. My Axion just has the base installed 105 AH AGM and when my wife purchased the van it was severely abused by the ill-informed RV dealer. Voltage was a 9V when we first looked at it! It has 200W of solar panels on the roof; but I had taken two long trips before I noticed that there was no charge controller installed! The local dealer put in the factory suggested MPPT controller and now even with the damaged battery I'm rarely thinking that I don't have enough battery capacity. If the sun is out at all, there is plenty of power. Even when the sun isn't out; the existing battery keeps the fridge running, the heater going all night, and the bathroom exhaust fan going during showers and during the day if when I use it along with a window cracked open to keep the temp comfortable inside. The 2000W inverter keeps all of my 110V electronics charged and even runs the microwave oven for the short cook times that I run it. Frankly, I over estimated how much power I thought I would need. I'm trying to kill this abused battery while its still under warranty, but that seems to be easier said than done! I plan to install about 200Ah of quality AGM when this battery goes.

Last note on towing... I tow a smallish utility trailer loaded with a motorcycle, mountain bikes, SUP's, and kite surfing equipment almost everywhere I go. I figure the think is probably around 1000 Lbs give or take. So it's not a big trailer, but I've had zero issues getting this in and out off road trailheads and sandy beaches and I'm almost at 14K miles by now.

Please post pics of your roof racks and additional roof vents if you put these in, I'm interested in this too!

[wincrasher]

Are you certain you only have a single 105 AH battery? A 2000 watt inverter would suck it down to low voltage in a few minutes. You shouldn't be able to run heat and a refrigerator all night either. I suspect you have more battery than that.

[kite_rider]

Smith101: I’ve now had my Axion (lith 400) a couple of months. I saw nowhere in the specs that the Alde 3010 would not provide heat and hot water above 3300ft. Altitude. So when I camped at 4000ft I had neither. The Alde part to fix this is not imported. So I have to hire someone to hack into the supply line and insert a regulator so I can rebalance fuel/air mixture. I talked to Hymer and they don’t want to participate in a fix. So, beware of depending on specs.

This is the first time I've seen or heard of this. I just rolled in from my last trip and thought about the last 'high elevation' place I camped. That would be the Curt Gowdy State park in Wyoming earlier this week (elevation approx 7,600 ft). After a great mt bike ride, the Alde system had piping hot water in the shower and with overnight low was in the 40's and the furnace kept the internal temps right where I set them. Similar performance everywhere else I camped in Utah and Colorado. I've not checked my exact model number, but the van is a 2017 model year.

The plan is to modify the system to pump heated glycol mix near the plumbing since I have had my plumbing freeze up after sub 20 degree overnight temps. I was inspired by member Avanti on this from a post about a modification to his van's hydronic system...

[warpig]

To jump in on the Axion talk but on a different topic, I am interested in owner's overall feelings about it. I am strongly considering a 2017 with lithium, volt, UG, and solar. This would be my first RV and I don't want to screw the purchase up. Have you had any problems? Would you recommend it? Any other info that you can share would be greatly appreciated. Thank you!

[kite_rider]

Originally Posted by wincrasher

Are you certain you only have a single 105 AH battery? A 2000 watt inverter would suck it down to low voltage in a few minutes. You shouldn't be able to run heat and a refrigerator all night either. I suspect you have more battery than that.

No, I'm not since I've never removed this factory installed battery to inspect it. I can say for certain that it is a single battery mounted under the chassis and looks to be about the size of a Group 27 battery. I just got back from my last trip; I departed on March 9th and the fridge has been on the entire time. The heater was used on many cool evenings and the water heater was used a lot. During the whole trip, I only plugged the system in one time at a state park just outside of Omaha, Nebraska last week. I tested the rooftop A/C there (previously I've only used it occasionally when it was NOT plugged in, but the van was running so I could rapidly cool the van) and I also tested the feature on the Alde system that uses shore power rather than propane for heat. It worked fine.

There was not a single time on this trip when the fridge stopped working or the heater didn't run all night. Note that I only use the 2000W inverter to charge my laptop and run the microwave for short periods of time (like 1 to 3 minutes) - otherwise it's off. So I'm not using the inverter at capacity ever and it's not on very long. An hour or two usually in the evenings.

There is a volt meter on the control panel and the voltage ranges from about 12.4V (when fully charged) to around 11.9V in the morning before the sun is out and when the heater is on and I've used the inverter to charge the laptop and cook some dinner and breakfast. Once the sun is shining I'm usually over 13V.

[booster]

You must drive a bunch essentially every day, or have good solar input?

[Smith101]

Originally Posted by warpig

To jump in on the Axion talk but on a different topic, I am interested in owner's overall feelings about it. I am strongly considering a 2017 with lithium, volt, UG, and solar. This would be my first RV and I don't want to screw the purchase up. Have you had any problems? Would you recommend it? Any other info that you can share would be greatly appreciated. Thank you!

The choice between lithium and AGM is about a lot more than just capacity. The lithium setup has some real disadvantages. To provide any power, AC or DC, the lithiums have to be turned on which creates immediate BMS parasitic drain of 60w per module. Which is why Hymer says to turn on only as much as you need. If you’re not drawing a lot of power, i.e. not using AC, an inverter powered appliance, or micro, you need only turn on one module. They also need to be turned on in order to charge from any source. You’re going to have to leave at least one on if you want the fridge to stay cool. So the 1920 usable watt/hours per module will dissipate quickly: in about 32 hours with no load. The inverter, when on, adds a parasitic load of about 100 watts.

To make matters worse, the solar never contributes to usable capacity or reduces consumption. With the lithium setup the solar only feeds the backup AGM battery which powers nothing except the BMS for the lithiums in case their capacity becomes too low to self start. All the solar does is keep the back-up AGM topped off. The solar would never send one watt to your fridge, for example. It’s likely the non-lithium setup would power the fridge far longer with good solar conditions. Solar on the lithium setup makes little or no sense, but the lithiums all come with it. I’m considering removing my solar panels to put in a fantastic fan.

The reason I went with lithiums is that I travel with a pet and I rarely stay in the same spot more than one night. And I travel through really hot areas in the southwest. If I need to leave my pet in the vehicle for a short time the lithiums are more than adequate to keep the air on. I also have the GU which takes about 90 minutes of driving to recharge depleted batteries.

My other issue is the Alde which failed to operate at 4000ft. Both Alde and Hymer say this is normal although some units, if you’re lucky, will work at higher altitudes anyway. So next week I’m replacing the 3010 with a 3020 which will cost about $2k. Anyone want a barely used 3010?

Other than that, the Axion performs its mission admirably although there are a lot of cheap, thoughtless touches. If you value shortness as I do—I park on the street in San Francisco—then the Axion is about the only choice for now.

[kite_rider]

Yes, I run the van almost every day; so the camper battery is usually fully charged each day. This is also why I don't like to plug in or connect a water lines, too much setup and teardown for my use.

[kite_rider]

Warpig:

+1 on what Smith101 says about the Axion. Unless you need that constant A/C when unplugged then I would avoid the Lithium and UG. Sad, since it seems like cool tech if it worked. I differ from him on the Alde, it's been better than I expected. Low power use consumption (I don't use the air circulation fan and like that you can turn it on and off) and it's really stingy on it's propane use. The propane seems to last forever...

In addition to the short length which is hard to find, the layout is unusual and not for everyone. Many class B's have a bathroom in the middle that splits the sleeping area from the dining/riding around area. That probably works well for most people, but in our case we wanted the larger common area even if it is a pain to setup and tear down the bed. Some people like to camp with the doors closed and stay inside to watch TV or something I guess. We like to have the sliding door open and visit while my wife cooks. This layout seems more inviting in this situation. Plus, I use this rig as a 'daily driver' and the extra space is good for hauling around SUP boards and my kite foil board which is awkwardly sized.

The only issues I've had are pretty minor. There is an aluminum heat shield that goes around the propane tank. This has rattled around and was already fixed once before it started again on the latest trip. Plus, the drawer latches are not strong enough to keep loaded up drawers from flying open on curves. I've been experimenting with various magnetic and friction latching schemes to correct this. Otherwise it's exceeded many of my expectations - which are probably low anyway since I'm coming from a VW Eurovan Camper..

[mumkin]

Just to let you know... when the solar is working, your reading will only be picking up the "surface charge." To get your actual battery reading, you have to wait for a few hours after sunset.

[falfal3]

I recommend the Axion with 400 amp hrs lithium, 200 watts solar and the ug 100% You will never know such freedom, regardless what the naysayers say. I love mine, perfect boondock vehicle whether 9000 ft in the mountains or in the horrible heat of the desert. Buy it and enjoy. Always remember, 17' 9".

[falfal3]

Same on every solar setup, right? Best part is the generator, right?

[falfal3]

Sorry to hear your Alde is defective, mine worked fine at Big Creek Lakes Campground, 9000 ft.

[Davydd]

Originally Posted by Smith101

The choice between lithium and AGM is about a lot more than just capacity. The lithium setup has some real disadvantages. To provide any power, AC or DC, the lithiums have to be turned on which creates immediate BMS parasitic drain of 60w per module. Which is why Hymer says to turn on only as much as you need. If you’re not drawing a lot of power, i.e. not using AC, an inverter powered appliance, or micro, you need only turn on one module. They also need to be turned on in order to charge from any source. You’re going to have to leave at least one on if you want the fridge to stay cool. So the 1920 usable watt/hours per module will dissipate quickly: in about 32 hours with no load. The inverter, when on, adds a parasitic load of about 100 watts.

To make matters worse, the solar never contributes to usable capacity or reduces consumption. With the lithium setup the solar only feeds the backup AGM battery which powers nothing except the BMS for the lithiums in case their capacity becomes too low to self start. All the solar does is keep the back-up AGM topped off. The solar would never send one watt to your fridge, for example. It’s likely the non-lithium setup would power the fridge far longer with good solar conditions. Solar on the lithium setup makes little or no sense, but the lithiums all come with it. I’m considering removing my solar panels to put in a fantastic fan.

The reason I went with lithiums is that I travel with a pet and I rarely stay in the same spot more than one night. And I travel through really hot areas in the southwest. If I need to leave my pet in the vehicle for a short time the lithiums are more than adequate to keep the air on. I also have the GU which takes about 90 minutes of driving to recharge depleted batteries.

My other issue is the Alde which failed to operate at 4000ft. Both Alde and Hymer say this is normal although some units, if you’re lucky, will work at higher altitudes anyway. So next week I’m replacing the 3010 with a 3020 which will cost about $2k. Anyone want a barely used 3010?

Other than that, the Axion performs its mission admirably although there are a lot of cheap, thoughtless touches. If you value shortness as I do—I park on the street in San Francisco—then the Axion is about the only choice for now.

Your describing Roadtrek problems not lithium ion battery problems. Other converters don't have those problems.

[BBQ]

Originally Posted by Smith101

The choice between lithium and AGM is about a lot more than just capacity. The lithium setup has some real disadvantages. To provide any power, AC or DC, the lithiums have to be turned on which creates immediate BMS parasitic drain of 60w per module. ...

Sadly this BMS 60w parasite is unique only to Roadtrek/Hymer ecotrek.
Most of the other lithium system on the market do not have so much draw.

To compound the problem, RT designed the ecotrek in 200AH modules. If you want 400AH of lithium, you have to have 2 BMS, with a combined draw of 120w !!! You will deplete your batteries by just turning them on