2108DS - How to boondock

[backtrack15]

Good. 3000/5500 is a good place to be.

[tinglett]

Originally Posted by Marine359

With the standard 60ah deep cycle, the fridge drains the battery in about 4 hrs. Makes it impossible to boondock. Trying to figure out an affordable solution without having to replace the fridge.

It seems to me that the first thing you need to do is learn how many Ah this fridge really pulls throughout the day. Perhaps someone on this forum has a good estimate if they already have one and have measured, or perhaps you can measure yourself. Once you know what it takes, I think you can make a much more informed decision about the battery+gen/battery+solar/absorption-fridge path to take. I searched and found the Dometic DMC4101. Not sure if this is the exact unit you have, but the specs online say it draws more than 15A DC input current. Ouch. Let's go with that as a minimum. One 24hr day of use at continuous duty is 360Ah. Hopefully this is just a max and the real duty cycle is a small fraction. In order to really know you are going to need to measure, but you can see where this maybe is going.

When I got my 2108DS a year-and-a-half ago I managed to find one only 6 months used at an incredible price. It was too good to be true in hindsight, and being a noob I'll admit I was a damn fool to buy it without consulting more help. But I got lucky, and since I decided I could use some of my "savings" to make it more what I want. That's why I plunked down the money for two lithium batteries. I know you saved a bunch on your TT and I'll suggest you may want to consider a little more investment to make it the way you want. Just my opinion. Something to consider is that you probably don't need to make changes instantly. Use it a little non-boondocking and make sure it's what you want first.

Also, if changing out the fridge is going to be a $2000 deal, maybe you can cross-check that a little by calling Winnebago for a parts price on it. I'm not suggesting this is a do-it-yourself project, but at least you can confirm what you are being quoted is in the ballpark, or if the dealer is trying to extract too much from you. Also, perhaps you can get some of that money back by unloading the 12v fridge on ebay. Might be worth looking to see if any have sold out there.

One final note. For this particular measuring I don't think a multimeter will serve you very well. The fridge is going to run off and on throughout the day and you can't stand there all day taking readings. You are going to need a real measuring device. For this experiment a cheap $18 Bayite (https://www.amazon.com/gp/product/B013PKYILS) would be adequate, but if you really plan to boondock you are going to need a good battery monitor for the long haul anyway. I really like my Victron BMV-712, but I've already found I never use the physical display. If you are comfortable with your smartphone, the Victron 500A SmartShunt should give you the exact same function at a much cheaper price. Just make sure you get the 500A (the smallest) as the larger shunts are totally unnecessary and are greatly more expensive.

[Dktexas65]

I have a 2015 2101ds. I believe you have about same but newer. The batteriy on the tongue i refer to as the "House battery.” There are 3 sizes. Group 24 and Group 27. These are 12 volt. Now, some people gang together in series 6 volt battery’s but I will leave that to the hardcore enthusiasts. I have a completely separated 200 amp/ hour Agm battery bank with a 1200 watt inverter, 10 amp noco battery charger, fuses, cutoff switches etc coupled to a 100 watt roof mounted renogy solar panel. All is mounted in my forward storage bay. I also have separate 100 watt renogy foldout panel I can hook up as well for 200 watts. On a good day I can get 6-15amps into battery’s per hour. I have two generators depending on time of year. A 2000 watt Honda type for winter and a 3200 watt invertor type for summer use to run ac etc. I can supplement the solar with the 10 amp battery charger. If you are not wanting to go solar, then I’d look into if you have room, putting two Grp 24 or better two group 27 lead acid in parallel on the tongue. Get a small generator and run 3-4 hours as necessary to top off. Search travel trailer amp usage and you’ll get idea of power consumption. The tv, microwave, ac run off 120v. Fridge on gas uses 12v for control panel, gas detectors, 12 v lights won’t consume much. The furnace fan runs off 12 v and consumes a lot of amps when running. Just add up what you realistic amp hour usage will be. Take the total amp hours of your batteries and divide by 2. Never run batteries below 11.2 volts. It can get extremely complicated and expensive with solar etc. a mr. Buddy heater on propane works well for off grid camping and you are not running your furnace. Lots of blankets help when cold. Open windows or run generator in summer during day. Good luck

[Old Navy]

Originally Posted by Dktexas65

There are 3 sizes. Group 24 and Group 27.

There are 3 types of people. Those who can count and those who can't.

Sorry, couldn't resist.

[Marine359]

Thanks to input from several here, we feel we saved enough by getting a killer deal on our 2108DS, that we can sink a few bucks into upgrading. We don’t believe we will spend more than 3 or 4 days at a time boondocking in one spot, probably on BLM. The 12v fridge is what it is, and we can live with it for now until we measure it in real world usage. A Honda 2200 is a must ($1100). We don’t want a complicated system, so I’m thinking of putting 2x 100ah SOK LifePo4 on the tongue ($1200). Then replace converter with a Xantrex 2000w inverter/charger ($700). It can charge the lithiums from empty in under 3hrs. So for about 3 grand I think we can get as good as it gets. Maybe add folding solar panel if we need it. If there’s a cheaper/better way to get what we need, I want to hear from you. But I do like the weight savings and no worry amperage drawdown of the LifePo4.

I’ve heard the Honda will run a 13.5 btu roof a/c if you load the the gen with fan only before firing up the a/c. If that doesn’t work, we may have to get an easy start.

One other question. Our Minnie comes solar prepped. I don’t know what that means. There is no plug outlet on the outside of the trailer. Just a small cover plate on front wall inside storage bay that says “Ready for Solar”. So, how do I plug in a portable solar panel?

[Old Navy]

The 2000W inverter can draw 170A continuous from your batteries. Your current 6 gauge DC battery wiring isn't going to work. Xantrex specs no more than 5' of 2/0 cable to the batteries, meaning a very short and direct route from the inverter to the batteries. You could install a penetration through the front cap, or maybe through the floor. Most people just co-locate the batteries with the inverter in the pass through storage.

For the solar prep, is the cover plate branded "Go Power" or Zamp? Mine is Go Go Power, and behind the plate are 4 10 gauge wires. 2 go to the roof, where there is an MC4 connection box for standard solar panels. The other 2 wires go to the batteries via the electrical distribution box on my drivers side frame rail. This panel is where you would mount your solar charge controller.

[creativepart]

Originally Posted by Marine359

I’ve heard the Honda will run a 13.5 btu roof a/c if you load the the gen with fan only before firing up the a/c. If that doesn’t work, we may have to get an easy start.

When I had a TT and Honda 2000i Generator it would not reliably start and run the A/C. It would run the fan and when the compressor kicked in the Honda would beep and drop into overload mode. This was 7 years ago and I know Honda has upped the output to 2200w. So, "maybe". I certainly have seen folks say it worked for them, but also plenty that said it didn't work for them, as well.

The big issue with running A/C from one 2200i Genset is that NOTHING else can be running. An RV likes to turn on the battery charger as soon as it senses a 110v power source. Obviously, you can't run the microwave or coffee maker or anything that is also a big power draw. So, while you may get the A/C to run you may not be able to do anything else within the RV.

And be sure that your RV Fridge is not on AUTO because it too would draw a ton of power from starting your generator.

We bought two Hondas and a paralleling cable. We carried both in the back of the tow vehicle and if we didn't need A/C we just pulled out and used one of them. But when we wanted A/C we pulled them both out, parallel connected them and had enough power to do almost anything AND run the A/C.

We looked long an hard at the Honda 3500i with remote starting - but heard from everyone that it was too heavy to lift it comfortably in and out of the tow vehicle.

[Marine359]

Originally Posted by Old Navy

The 2000W inverter can draw 170A continuous from your batteries. Your current 6 gauge DC battery wiring isn't going to work. Xantrex specs no more than 5' of 2/0 cable to the batteries, meaning a very short and direct route from the inverter to the batteries. You could install a penetration through the front cap, or maybe through the floor. Most people just co-locate the batteries with the inverter in the pass through storage.

For the solar prep, is the cover plate branded "Go Power" or Zamp? Mine is Go Go Power, and behind the plate are 4 10 gauge wires. 2 go to the roof, where there is an MC4 connection box for standard solar panels. The other 2 wires go to the batteries via the electrical distribution box on my drivers side frame rail. This panel is where you would mount your solar charge controller.

Wow,
Thanks, that gives me a whole new perspective. I had planned to mount the SOKs on the tongue, but after reading your post, makes more sense to mount them in the pass thru, and install inverter next to batteries. That frees up the tongue to mount a box to carry ground tackle, and gear like chocks and Andersens. With that setup, maybe it makes sense to install standalone inverter, transfer box, and replace converter charger with lithium compatible unit. That would save several hundred dollars.

[pj48009]

My only experience in dry camping was a couple weeks ago on the way to Florida. We stopped at a farm in Tennessee for three nights to visit a relative. I prepared by replacing the joke off battery that came with our trailer with a group 31 deep cycle from batteries plus. I respected the advice of multiple batteries but decided to experiment with this. Dry camping will be rare for us so I didn’t want overkill. I bought a Honda 2200 generator and it might have been the last one in Detroit. There was a massive power failure that made bad timing for us. I’ve been wanting a generator for a while now and this one should fit us. Easy to bring with and can power essential items in our home, cottage or rv. If I need more power I can purchase a second one. So our experience went fine. The group 32 was plenty to operate lights, pump, and furnace. It actually snowed in Tennessee and it was in the low 30s at night. The battery never got under 50 percent with the generator running an hour or so in the morning to run the coffee pot and charge the battery and a couple hours in the evening to watch tv. I’m sure now that I have a generator I’ll never have a power failure again. 😀

[tinglett]

Originally Posted by pj48009

I’m sure now that I have a generator I’ll never have a power failure again. 😀

Ha, I bet that's true! But nothing wrong with that .

Do you have the fridge that can run on LPG? I've found it has a very low current draw. But I'm hearing the 12v fridge may be multiple times what the furnace uses (15A?). Yikes. Still, it doesn't run all the time so maybe it isn't as bad as I think.

My #1 advice is to get a battery monitor if you plan to dry camp a lot. @Marine359, I forgot to mention that over in the micro-minnie thread. This is a better place for the discussion anyway (just catching back up!). A battery monitor would be my first purchase if I could start over. Do some "camping" in the driveway, or disconnect if you are at an RV park and measure how it goes. That knowledge will be huge for driving decisions for all these expensive upgrades.

[pj48009]

Yes I have an absorption fridge propane and 120 volt. If and when it fails I’d like to get a compressor fridge. Your experience is telling me to get a 12volt / propane instead of the 12 volt only.

[Marine359]

Thanks Tinglett,
By experimenting in the driveway, we found (duh) that our dometic 12v only fridge does not draw down the battery nearly as much when we pre-chill the fridge on shore power. After the fridge has been on for about 2 hours, it only cycles every 10 minutes or so when empty, and every 12 minutes when full of cold foods. So we’ve decided not to swap out the fridge for a combo unit. The 12v fridge is 8 cu ft.; much bigger than a 6 cu ft combo unit.

Likely will swallow hard and pull the trigger on buying a Honda 2200i, Xantrex 2000w inverter charger which can be programmed to charge between 5 and 80 amps, and a single 200ah SOK LifePo4. The SOK can take a 60 amp charge. Over our budget, but installation is far less complex than going with a stand alone inverter, transfer switch, and replacement converter charger. And the overall cost is not that much different. Plus you’d have to figure out a way to switch off the charger when inverter is on.

Installation on the DC side should be simple. It’s on the AC side that I’m worried about not having the skill set. By mounting battery and inverter charger in pass thru, there’s a very short cable run to connect the two. Then I suppose you have to run two AC cables through (under) the chassis to the breaker panel; Ac out and Ac in (shore power).

I would surely like to hear from somebody who has done this as a DIY. Paying somebody to do it could cost another grand. Thanks for all your help.

[tinglett]

Originally Posted by pj48009

Yes I have an absorption fridge propane and 120 volt. If and when it fails I’d like to get a compressor fridge. Your experience is telling me to get a 12volt / propane instead of the 12 volt only.

I'd agree if you dry camp frequently...but I think you said the opposite. As Marine359 just noted the compressor fridge is much bigger. I'd track what he's finding. Maybe we'll learn this fridge doesn't consume as much power as we thought and soon I'll be wanting one too That said, hopefully your fridge won't fail on you anytime soon!

[Greg Morrow]

Make your ac/converter can charge a lithium battery, most rv converters can't. Expensive mistake if your not sure.

[tinglett]

Originally Posted by Marine359

Installation on the DC side should be simple. It’s on the AC side that I’m worried about not having the skill set. By mounting battery and inverter charger in pass thru, there’s a very short cable run to connect the two. Then I suppose you have to run two AC cables through (under) the chassis to the breaker panel; Ac out and Ac in (shore power).

This is the thing to do if you want a real fast charge. I only get about 30A through my 6 AWG from the converter. I have connected a battery direct to the converter and found it really can do 55A, so I'm fairly confident in blaming the long thin wire run.

In my rig there is a 120v outlet directly above on either side of the murphy bed, so there is 120v wiring down in the storage bay. It's not the right circuit but may do fine. Consider that 90A at 14.5v is only 1300 watts. That circuit should be able to handle it depending on what else is sharing the line. Just a thought.

One other thought is if you really want to charge that fast. I know this sounds like a silly question, but as I was playing with my new Honda 2200, it occurred to me that it runs a lot louder at that higher power draw. So is quieter for longer better than short and loud? I really don't know, but the thought stopped me in my "upgrade thinking" tracks.

[tinglett]

Originally Posted by Marine359

So we’ve decided not to swap out the fridge for a combo unit. The 12v fridge is 8 cu ft.; much bigger than a 6 cu ft combo unit.

BTW, I keep forgetting another important positive detail about the 12v fridge. This fridge will (should) run while you are on the road. No LPG issues to worry about. That's something that might be pretty big for some future road trip. It also doesn't have the ammonia/fire risks that an absorption fridge has. Hopefully, for my own sake, these risks are rather low .

[Old Navy]

Originally Posted by Marine359

One other question. Our Minnie comes solar prepped. I don’t know what that means. There is no plug outlet on the outside of the trailer. Just a small cover plate on front wall inside storage bay that says “Ready for Solar”. So, how do I plug in a portable solar panel?

I was out in the trailer, so snapped a few pics of exactly what "Solar Prep" includes on my 2401RG.



2 MC4 connectors on the roof



This shows what is behind the panel in the pass through storage. 10 AWG wire running from the roof MC4 connectors and to the batteries, via the frame mounted electrical box.


I also pulled a vent and verified my roof decking is 4'x8' sheets of 3/8" OSB, with trusses 16" on center, sort of. Some trusses are off to accommodate roof penetrations. The top boards of the trusses that the roof decking is attached to are 1x2's.

[Marine359]

Tingle55,
If you install a Victron mppt Bluetooth solar charger controller, do you still need a Victron negative shunt battery monitor? Wondering if both display the same info. If they do, the Victron mppt 30amp controller costs $226, and the Victron neg shunt Bluetooth monitor @ $131. Would be redundant wouldn’t it?

I wanna spend my money before my battery arrives, but I can get confused.

[Marine359]

Sorry Tinglett,
Spell checker changed spelling of your name

[creativepart]

Originally Posted by Marine359

Tingle55,
If you install a Victron mppt Bluetooth solar charger controller, do you still need a Victron negative shunt battery monitor?

Yes, you need both. The units do network together and show the battery's voltage and temperature on each part of the App. But all the other details are separate.

You can get an upgraded display that will group everything into one app but you still have to have all the individual Victron devices installed. There is no one device that does everything.