Spray Some Paint
While our buildout transforms a cargo van into a RV, it doesn't need to look like one. Most RV's you see out there aren't exactly in the most understated of tastes. Don't get me wrong: I have no problem with whatever someone chooses to buy. We seriously considered purchasing a used pre-converted van ourselves. Who cares what it looks like if it works well? That said, when I'm going to all the trouble and spending my precious time with my one and only life to build our van out, I want the end product something that matches my sensibility. Unfortunately, the various sundry parts such as vent covers and intake valves we will be installing on the exterior of the Sprinter universally come in beige or almond-ish colors. Mounted to our blue grey rig, they will be the focus of the eye. Not exactly what I want to draw attention to. I'm going to solve that problem by painting most of the exteriorly added parts with Plastidip, an idea I picked up from SprinterVanUsa.com Preliminary results look pretty good.
I'm a little concerned about coating the hot water heater vent with Plastidip. According to this site, however, it should be fine up to 200 degrees. The close-up below shows the popcorn texture that builds up with several coats (4-5 recommended, it currently has two). Supposedly it can also be peeled off, which makes me think that it might not wear well. We will see how this product does. I won't be very surprised if I have to touch it up over the years.
The above image (slightly out of focus--sorry) gives a little better view of the texture. It feels rubbery like a tool handle. The orange peel surface looks pretty good. So far it looks like it was applied at the factory, but give me time, I'm sure I'll drip something on there in a subsequent coat that looks bad. Plastidip can be applied with a legitimate spray gun instead of a crappy rattle can, which I'm guessing would improve things a lot if you were doing many pieces.
Another coat applied. You can see that it looks rather uneven when it goes down. Those seem to even out as it dries. While it doesn't really show, the inside of the frame of the hot water exhaust door was still 80's almond, so I put a coat down on the inside just so it looks totally done. I'll add two more coats to the exterior before calling it good. One can is good for about 3 coats of this 18"x18" door. People Plastidip their entire car--they must not use a rattle can to cover that volume!
Getting going on the Electrical System
The electrical system is the most complicated & easy to mess up of all the steps in our build out. Mess up a cabinet? take it out and redo it. Mess up the electrical? could have serious consequences. We are lucky to live just a few hours drive from a reputable solar upfitter, AM Solar, residing outside of Eugene Oregon. I'm not totally afraid of doing it myself (AM Solar is very friendly to the do-it-yourselfer--you can just buy the kit I'm having the install), but this is one key area where in the choice between my time and my money, I'm choosing to have my time. We will be farming nearly all of the electrical out to them. Here's an overview of what we will have done:
- Three 160 watt solar panels installed on top of the van, with a junction box that will tap the roof down to the controlling system and batteries.
- 200 amp hours of lithium batteries. This is likely the single most expensive purchase of the buildout not counting the Sprinter itself. Lithium has come a long way. I'm really happy to be in the market when I feel comfortable that Lithium is a viable option. It's not been very long that that has been true. Right now, in my opinion, the biggest downside of Lithium is price. I'm not going to write much about this choice because things are changing so quickly it would be of little value in helping you make your decision if you are trying to figure out your own system.
- A lead from the motor alternator (along with various safety gadgets) so we can charge the house batteries from the engine.
- A pure sine wave inverter. This converts the 12v DC to 120v AC. We don't have pressing 120v needs so this inverter will be small.
- We won't be installing a inverter that can charge our batteries from shore power (note: a lot of RV terminology and tackle comes from the boating community that pioneered a lot of this gear).
This generation and storage set up will service the following load:
- various 12v LED lighting runs, interior and exterior.
- A 12v, 5A fridge. I have not settled on the exact model, but it might be this one.
- Hot water and stove ignition (low draw, 12v)
- The Espar D2 system I've installed (1A running 'normally')
- Ad hoc 120v plug in. This will service various charging wall warts or the rare 120v appliance, like a computer monitor when I work remotely.
Our load will be pretty small. The fridge likely won't draw 5A very often, so our 200Ah of battery, charged to 100% on the drive to our destination by the alternator, should stay well into the useable range backed by the solar input for the typical times we have no need to start the engine, a week maximum. With strong solar input, I'm guessing we could run quite some time with the battery bank and the solar generation. It will be interesting to see how this plays out: I think I've really overkilled our system, but maybe we really want to run 120v doo dads regularly.
Dropping off the Van
We are lucking out that AM solar is both relatively close and able to book a slot for us, as they can be quite busy. We received the van two weeks ago, it will spend a week down there, then, magically, a big chunk of work will be done! We met Cody today to go over the spec's we've been emailing back and forth. Here's a not very good picture of the work area they have. It looks like a pretty comfortable space to do these installs. Most of their installs are retrofitting into class-A motor homes (man, I shutter at what it must cost to solor-ize a big rig). Our's is a small job in comparison. All the various sundry wirings and gadgets will be secured to plywood so I can move bits around during the remainder of the buildout.
In a week, I'll go over the details of the stuff we had installed, for now, a quick picture of the 200Ah gang of Lithium cells:
Throughout the week that AM Solar has had our Sprinter, they have communicated with me almost daily via email. They deliver truly top notch customer service. Cody, the warehouse and installation manager, is a really good communicator. He asked about a few details, then sent these two pictures on potential solar panel layouts. One allows us future expandability for another panel, the other leaves enough space for a second vent, something I talked to him where we were down there as a possibility. We chose the second vent option.
The Table and Some Prototyping
Back on the homepage I described setting the front seats on swivels so we can use them as our dining room. I'm making a little table out of 1-1/2" bamboo ply that will match the other bamboo cabinets we will be installing. The table will mount to a removable leg in a base affixed to the floor. As previously mentioned, the seat height raises about an inch and a half with the installation of the swivels. When the seats face aft, our feet dangle in the air while our knees would be uncomfortably tight on the bottom of the table. I'm raising the table a bit by mounting the post receptacle on a maple block that will be glued to the bamboo.
As you can see, the table is pretty small (25"x17"); it's a design decision we will have to live with. The table is barely large enough for two people eating. In a pinch, we can probably play cards with four people, but I wouldn't be surprised if that doesn't work out very well.
I'm prototyping things I'm not super familiar with. Most of the structural components such as the bed platform and the shower will be made out of 1" 8020 extruded aluminum. If you are unfamiliar with this product, it's basically aluminum bar that's designed to be cut and bolted together. It's used for all sorts of applications. I purchased some 1.5" 8020 to prototype. This particular example shown below used bar stock with t-slots on all four sides. I rabbit jointed the edges of a bamboo ply panel to fit into one t-slot with the result looking like a frame and panel in wood. I've decided through this prototype that 1.5" is total overkill: I'll be using 1" 8020. Still, the prototype gives a pretty good sense of working with the materials and how it will look in the van.
The bottom part of the picture shows a prototype wall panel. I cut the rough 1/4" ply with a jigsaw, then used spray adhesive to affix a headliner (thin foam used in cars), then the finish fabric is applied. I bought a yard of sample fabric of the same make as we will be using (the only difference is we ordered creme/tan). We are using Crypton, which is a highly recommended upholstery fabric used typically on furniture.The walls and ceiling will be mostly covered with panels constructed this way. I learned a lot from doing two prototype fabric panels such as this. The plan is to do the rear doors first--they can be done at any time since there is no electrical or plumbing runs through them. I'll feel a lot more confident after working out my methods on the first fabric panels. I'll post more regarding the details of making the panels when I fabricate them.
The table is ready for some finish, the bane of my existence
Picking up the Sprinter from AM Solar
Drove down to pick up the rig with all the electrical put in. It's pretty fancy
We aren't going to have that may just-add-water moments with our buildout; I'm going to savor this one.
I'm up three feet on my porch taking this next photo. You still can barely see these panels. They are pretty low profile.
Below illustrates the drop down into the van from the solar panel junction box. Some 4 AWG runs to the panel.
AM Solar installed the components on some plywood with some extra wiggle room so we can move the panel around to insulate behind, install the floor, etc. In retrospect, I wish I'd insulated prior to having them do this as that will be sort of a pain now. Installing the van floor will be more of a headache working around the heavy bank of batteries and all the cabling tucked away nicely at the moment.
This panel is installed behind the back drivers side wheel well. Ultimately, most of the gear will remain here. The plan is to allow access to this panel by opening the rear doors, though everything to the right of the DC fuse box will get moved into the cabin.
There's a lot going on here! Let's label the picture:
Here's what's, starting from the top left:
- Solar panels to solar regulator main disconnect. This switch cuts off the inbound juice from the panels up top.
- Solar Regulator. This Blue Sky Solar Boost 2512ix-Hx unit monitors the power coming in from the panels on the roof, making sure all is well. It's not lithium battery specific so it has some functions that don't apply to our batteries (non-lithium batts need different kinds of charges as they get fuller). This unit uses MPPT (Maximum Power Point Tracking) technology, allowing it to potentially get more juice from the solar panels. We have 300 watts (max) of solar as 12 volts. The panels actually put more volts (in the 16-18 volt range), but the batteries really want to receive and hold a voltage much closer to 12v. MPPT controllers are able to step the higher voltage from the panels down to the 12v the batteries want, converting the extra volts to amps in the process. In essence this technology allows you to get closer to the true wattage output your panels are producing. The battery monitor described below actually shows the difference between what it's getting from the panels and what it's sending to the panels, which is pretty cool. In short, the solar regulator optimally pairs the panels to the batteries as conditions change.
- Solar Circuit Breaker. This 30A breaker ensures that we don't start a fire by passing too much juice from the panels through the system. As a practical matter, this is overkill because we won't ever be handling close to 30 amps.
- Inverter Circuit Breaker. This sits between the batteries and the 120v Inverter, making sure the maximum input of the inverter is not exceeded, which is again overkill because we won't ever have anything close to 60A.
- DC fuse box. All the positive 12v DC runs will terminate here. There's space for 12 runs, which should be plenty I hope. I plan on running a lot of isolated runs, though.
- 120v outlets. I had AM Solar hook up the 12v outlets so they could be tested. they will get moved somewhere else after I'm positive where they are going to go.
- Main Controller/Battery Monitor. This is the brain of the system, a Blue Sky IPN ProRemote. It specifically pairs with the solar regular (they work together in a solar system to regulate battery change/discharge). It monitors the battery levels and voltage specs. If will trip the system off should the batteries run below 20% or the voltage drop below spec or go above spec. Should either of these things happen the momentary reset button will flash red for like two minutes giving you the option to do something. For example, should we draw the batteries down to 20% capacity, the controller will trip, the reset button flashing a warning/red. We could then remove the load from the system which will keep the batteries from drawing further, or turn on the van engine to change the bats from the alternator. The main controller and reset button will get moved into the cabin at some point.
- (back over to the left) Main Disconnect. This physically breaks the link between the batteries and the the rest of the system.
- Battery Master Controller Each cell in the battery (there are eight) has a mini-controller that monitors the state of that cell. If a high voltage is detected (which may occur for example if the vehicle alternator sends current above spec), the individual cell controller will burn off the excess voltage by sending the juice through a little on-board resistor. In addition, the entire battery is seen as a single unit by this master controller. It can also disconnect the system by activating the relay to the left when, according to AM Solar, "any cell (or supercell) is below 2.6VDC (approx. 10.4VDC/Batt) or over 3.65VDC (approx. 14.6VDC/Batt)"
- 120v Inverter. This SureSine 300 unit converts the 12v DC power to 120v AC in a 'pure sine wave'. This is supposedly good for some kinds of devices, particularly those using motors. This inverter provide 300 watts continuously of 600 watts for 10 minutes before needing a rest. We can't run a hair drier off this, but the various 120v odds and ends we are likely to want on the road (like a full sized computer monitor) will be well within this units capacity. We opted to not add shore power, so we can't plug our van into an 120v source to charge the batteries, which I doubt we would ever use. There's a big price jump with pure sine inverters from this class to something in the 1000 watt range, so we decided to go with the smaller unit. We might find this to small, but, like I've mentioned, we don't have pressing 120v needs now.
Not pictured, there's a line running from the van alternator back to the pictured system. You can see one of those lines going into the main disconnect. This alternator line runs into a disconnect switch of it's own that's mounted on the driver set pedestal.
There's also a line that runs from the house batteries/master controller back up to the van battery. If the house battery is full, a trickle charge is sent up to the other battery. If the van alternator goes out when we are out somewhere in the boondocks we could just wait for the solar panels to send enough juice to the van battery to turn the engine over. This is one of those add-on things that are probably a waste of money much like the trailer harness we ordered from the factory: I'll be surprised if this ever gets used. Moreover, getting a trickle charge from the solar to the van battery also could mean that we could be ignorant of a dead alternator since the van battery might get enough charge to turn the engine over and run the van's electrical system for some time. It wasn't expensive, but I don't think we really need it.
I took off the top protecting ply lid to expose the individual cell connections
Over on the right, you can see the lead for the battery internal temperature probe. Lithium batts do not like being charged below freezing. You can discharge below freezing, but you can't charge them. The battery master controller picks up the temp so you know to turn off the solar (and alternator if it's on) & not charge the batts when it's freezing.
Firing up the Heater
With the electrical installed, I can finish the the heater install. This requires wiring up the power to the unit and hooking up the temperature controller. The controller comes with all the connector parts to make a quick disconnect, which is nice. It's slightly confusing, though, because there's an extra wire on the heater lead compared to the controller side. With some soldering, the controller turned on and the the fuel pump started clicking. Luckily, I read that it takes a few cycles to bring enough fuel up to the burner and clear the air out of the line before it fires up. If I hadn't read that it takes a few cycles I'd of sweated things a bit. In roughly 20 minutes heat started pouring out. Rock on!
I found one issue on startup: my exhaust pipe that pokes out about halfway into the slider door allows exhaust to enter the cabin. It's immediately noticeable. I'm going to look into extending the tailpipe so it reaches farther back, like into the rear wheel well. For the time being, we will be keeping the slider closed when the heater is on (which is what we would be doing anyhow).