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Discussion Starter · #1 · (Edited)
Hi folks - apologies if this is the wrong forum for these Qs - I did searches and couldn't find a relevant thread (thx for links if already discussed!)

I'm considering a campervan conversion diy project with a Metris.


I want to use the van's car stereo, heater and possibly AC (on rare occasions) from a battery/power system when the van engine is off, rather than installing independent heating/cooling system. I will have a large fan installed in the roof, but out in the desert SW US I can envision sometimes wanting the AC. I think the heater in the cab will probably be sufficient to heat the whole van enough (going to super insulate the entire vehicle), I'm really only thinking this would be a 3 season campervan only.



I'm planning on ~360-400ah lithium Lifepo4 batteries and a small portable generator (probably the small 2200w Honda). Ceiling fan, small microwave, small portable fridge and LCD lights will be main demand on the power. I will have ~360w solar panels. There is other power demand for astronomy gear but I'll calculate and add more batteries if needed, thinking right now this will be enough all up.



If I'm reading correctly on sprinter forums - a 2nd alternator under the hood will allow me to run the car stereo, heater with engine off? So I'm thinking an alt/toggle switch in the cab where I flip electrical to default alternator as shipped stock in vehicle, then when not running engine (camping) switch to 2nd alternator to have power to everything - or is that even necessary? I'm not sure about AC - sounds like generator would have to be running for AC, although wondering if the 400ah battery store would be sufficient? How can I calculate the AC pull and if my battery/generator will be enough?



Do I understand this correctly? Is there any good write-up how to do something like this in a Metris?


Thanks
 
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Discussion Starter · #2 ·
Meant to add w/ Qs (but edit time ran out on original post) - is there enough space in the engine compartment to mount a 2nd alternator in a Metris? What other concerns should I be thinking about?
 

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2019 Passenger
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Sounds like you maybe dont own a metris and maybe this might be your first car? I could be wrong.

No AC without the engine running.

Heat is best from a fuel. There is a gasoline heater and a propane heater with discussion on the forums.

Personally, I'd try to limit my power needs as a general practice. There are a lot of things you can do to eat and keep food that doesn't need a microwave or a fridge.

If you are camping in legit places that permit generators thats probably a good option, but storing fuel in the van on a regular basis is not my favorite thing.

While lithium batteries are super awesome, they are expensive and potentially dangerous. That not the kind of thing I want anywhere near me when I am sleeping. Of course, they are an option, but "normal" batteries are a lot easier to manage and source.
 

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2016 Cargo converted into a camper van
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I don't believe there is an option to put in a second alternator in the Metris. Even if you could, you'd still need the engine running to power it so the main alternator would be available. I'd think you'd be seriously, seriously challenged to safely add a second alternator as a DIY project.

You need the engine running to get heat- it uses heated engine water in the cooling system for heat. If you want heat without the engine running you'll need to use a gasoline heater (I have a Webasto that draws from the fuel tank), a propane heater such as a Propex, or an electrical heater. An electrical heater will rapidly drain any storage battery that you install so realistically you're looking at a generator.

Vehicles are tough to insulate well due to doors, windows and their metal structure. The Metris has curved walls making it much more difficult to insulate than a Sprinter with its flat sides. Adding more than an inch of foam in the ceiling or upper part of the walls cuts into the living space, as does any insulation on the floor.

A solar panel will help keep up with electrical demands but you'd be optimistic to expect it to power a frig, mircowave and fan if you use them much. A battery to battery charger will provide a lot more amps to your aux battery if you've driving on a regular basis.

The Metris is small compared to a Sprinter, downright tiny compared the larger models. Your plans seem pretty ambition for a Metris.
 

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First of ransom ridge is right, you can’t power the heater without the engine. Automative heat is a byproduct of the waste heat created by a running engine.

I disagree that the Metris is inherently too small for a van camper... but I do think it is too small for a person who seems to want all or most of the convienences of home in their camper. It is the kind of camper where you have to set it up to be converted every time you change modes (i.e. your bed is your sofa and your dining seat, your portapoty will have to be stored and pulled out, an enclosed bathroom is almost out of the question, and showering is best done with a long hose and a curtain hanging from your tailgate... while you are outside. And your kitchen will be positively puny.)

If that’s what you want the Metris might work... but I think you’d be better off with at least a 144” high top Sprinter. And a generator.
 

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I don't know about a second alternator but the Metris has an option for a second battery that charges from the main alternator once the main battery is fully charged. The Metris is, indeed, small for all the options you want to add. However, I've saw a smaller van nicely fixed up, but that worked only because it had sleeping for just one person. There are a few places that do Metris camper conversions so examining their web sites can give you an idea of some of what is possible.
 

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While I’m at it, keep in mind the Metris uses a smart alternator which shuts off above a certain battery level and uses regenerative braking for further charging (once upon a time GM actually called this a “mild hybrid”).

Diesel, gas, and propane heaters are extremely effective devices, especially in a well insulated van. Further in the US the only real advantage of a Metris over a larger van is being able to park in more (but not all) garages. A four-cylinder diesel Sprinter will probably net you similar fuel economy with more space.

If you can find a short wheelbase high top Ram ProMaster with the Fiat Commercial diesel (it’s no longer available) and auto-manual transmission that is probably the ideal base for what you want. The ProMaster is 84” wide and can contain most people quite comfortably in a transverse bed, leaving lots of space for a wet bath, kitchen, and all the other stuff you need.

The normal ProMaster combines the disadvantages of FWD in a heavy hauler with an overstressed crappy Chrysler minivan Powertrain. Used as a camper with the durable commercial diesels That is one of Fiats big strengths, it’s actually a great van. If I was starting a van conversion camper it would be a likely starting point for me (MB Sprinter residuals are a bit strong).
 
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