Need Solar Advice and Help!!

[lewster]

Originally Posted by DKB_SATX

What drboyd said.

You want a Danfoss compressor fridge if you don't want to deal with an ammonia-absorption fridge. If you really want to go super-efficient and you're moving things around, you might look into the top-loading units, since they take less of a hit when you open the lid than a front-loading unit takes when you open the door.

I'm planning to use a Danfoss fridge in the trailer I'm renovating because they cost about the same as an ammonia absorption fridge but work better in hot weather, and nice new propane fridges still use 12v power for the controls. If I had an old-school dumb propane fridge with no 12v control board to die and/or eat battery (like the one in my 24' Argosy) I'd probably keep it. It's marginal in really hot weather, but I've learned not to camp in weather like that.

Yes, the Danfoss fridges cost more than the crappy 120v dorm fridges. TANSTAAFL.

Also look at the Isotherm units from Indel Webasto Marine. They are at iwmarineusa.com. Great units that I have had great used reviews.

[idroba]

Originally Posted by tallredboned

ok. Thank you....

so now here is the question...

What energy star fridge should i get. I am not...I repeat NOT...doing the propane fridges. I have heard some absolutely horrible stories about them, and they kind of defeat my purpose with the life i am living.

I want a solar unit. So i am looking at energy star fridges, this one in particular...

http://hhgregg.scene7.com/is/content...gg/HNDE03VSpdf

it is very low amp usage, and will be enough room in my remodel.

Remember i am going to be running 300w panels with 1000w inverter.

That one uses a very high amount of energy, 420 kWh a year. The one in your second post uses far less, 270 kWh a year. There is a lot of difference between them, the 270 one being much better.

Also remember that most of the small refrigerators use the sides and top for heat dissipation, and must be free standing units, not built into a cabinet with no clearance on the sides. You need a refrigerator with coils on the back. If you don't see them you cannot build the refrigerator into a cabinet.

[drboyd]

Originally Posted by idroba

<snip>
Also remember that most of the small refrigerators use the sides and top for heat dissipation, and must be free standing units, not built into a cabinet with no clearance on the sides. You need a refrigerator with coils on the back. If you don't see them you cannot build the refrigerator into a cabinet.

You also can't block air flow past the coils on the back. The air has to have a clear path in at the bottom, up along the coils (as hot air rises) and out at the top of the coils.

[hippygypsy]

OK I am almost done with my decisions...research and reading everything i can find while i restore this airstream;

I have decided on this system from Canada:

Solar Panel Kit Panneau Solaire 300W 300 w Watt 3 100 w MPPT Poly 12V RV | eBay

I spoke to everyone i could and got some really good advice...and some really bad advice also.

That part is scary.

I am still a little confused as to why i need an inverter if the trailer already has outlets?

do you plug everything into the inverter?

that makes no sense.

I am now on to the final questions...

Battery size.

I am looking a 2 12v batteries on ebay...

Power Sonic 12V 35Ah U1 Deep Cycle AGM Solar Battery Also Replaces 33ah 34AH 3 | eBay

I was told i need 2 6v batteries, so i do not understand what the difference would be with 18v panels...so i am going with the larger battery.

Yes that may sound rhetorical but it is a question.

[DKB_SATX]

re: the inverter: All of the 120v outlets in your '76 Tradewind (at least in original configuration) are supplied only by power coming in from the "shore power" cord. The battery (one in the original configuration) only powers the lights, vent fan, furnace, water pump and the 12v "cigarette lighter" style outlets. Without an inverter, you wouldn't have any 120v AC available unless you're plugged in.

In the simplest application of an inverter, you could just plug in 120v loads directly to the inverter as needed. You can in theory plug the shore-power cord into the inverter *IF* you are careful to disconnect the converter-charger and assure that the refrigerator and water heater are using propane only. The next option would be to add an outlet or two dedicated to the inverter, which is how new Airstreams are configured.

re: recommendations about battery options: The 2 6v batteries in series offer long life and good storage capacity compared to a pair of 12v batteries of similar exterior dimensions using similar technology. The panel voltage has nothing to do directly with the battery voltage, the charge controller manages that for you, charging the batteries at appropriate voltages even as the panels' output voltage varies somewhat in different conditions.

[idroba]

Originally Posted by tallredboned

Battery size.

I am looking a 2 12v batteries on ebay...

Power Sonic 12V 35Ah U1 Deep Cycle AGM Solar Battery Also Replaces 33ah 34AH 3 | eBay

I was told i need 2 6v batteries, so i do not understand what the difference would be with 18v panels...so i am going with the larger battery.

Yes that may sound rhetorical but it is a question.

The 35 Amp hour batteries you show are way too small. Even one group 24 battery has about the same capacity as two of those small ones. And most current Airstreams come with two group 24 batteries as standard equipment, and I consider them as marginal.

Two 6 volt golf cart batteries in series (to produce 12 volts) have a total capacity of about 220 Amp hours, which is 3 times the capacity of the two little 35 amp hour ones you have mentioned. Golf cart batteries at Costco or Sam's club are in the range of $90 each.

[hippygypsy]

aaaaaaaaaahhhhhhh!!!!

So dedicated 120 inverted powered wall sockets is the next question. I want to run a TV on occasions...so i need to plug that into the inverter?

Second i am going with the Girard instant hot heater and the fridge is already 12v.

So how i am looking at those plugs as wired directly to the inverter...or did i miss something?

[dkottum]

Originally Posted by tallredboned

aaaaaaaaaahhhhhhh!!!!

So dedicated 120 inverted powered wall sockets is the next question. I want to run a TV on occasions...so i need to plug that into the inverter?

Second i am going with the Girard instant hot heater and the fridge is already 12v.

So how i am looking at those plugs as wired directly to the inverter...or did i miss something?

There's some hit and miss designing going on. Whoever is designing your solar system ought to have knowledge of RV electrical requirements, and that solar will be your only power source.

Certainly no expert whatsoever, but I would be surprised if this is practical or even possible without propane for heating requirements. Am I underestimating RV solar?

[DKB_SATX]

Originally Posted by tallredboned

aaaaaaaaaahhhhhhh!!!!

So dedicated 120 inverted powered wall sockets is the next question. I want to run a TV on occasions...so i need to plug that into the inverter?

Second i am going with the Girard instant hot heater and the fridge is already 12v.

So how i am looking at those plugs as wired directly to the inverter...or did i miss something?

If you've chosen a Danfoss-based fridge like the Vitrifrigo or the Dometic Tundra or similar, you're home free there. A 120v TV will need to be powered off the inverter if you don't have a shore power connection. If you think all the plugs are (in their original configuration) connected to any sort of inverter, you're missing something. It's certainly possible to wire in an inverter for them as a modification, or to add a dedicated inverter plug or two. Are you looking at an original wiring diagram or a design document from some solar proposal? Perhaps you're confusing the converter-charger (Univolt) with an inverter?

Another alternative is to find a 12v DC TV, there are a few but there's much better selection in the 120v AC sets.

[switz]

Our 2013 25FB International Serenity had the factory installed 600 watt inverter. The two TV power outlets and one under the dinette were the only ones that got 120Vac from the batteries. Our dealer installed single 150 watt solar panel could NOT bring the batteries to a full charge with full sunshine all day after the furnace ran at night at the Albuquerque Ballon Festival last October. We had to run the Honda 2,000 watt generator about an hour to get the batteries to 100% capacity for the next night's furnace run.

We ordered our new Classic with only the 50 amp service upgrade. Thus all the trailer's 120Vac outlets lack power when the service cord plug is pulled from the service pole beside the trailer. Everything has to run off the batteries at 12Vdc and or propane.

Now the Classic is undergoing a major solar system installation that includes eight 100 watt solar panels with a Magnum MS2812 pure sine wave inverter/converter and a TriStar 60 MPPT solar charge controller connected to four Lifeline 6Vdc 300 amp hour batteries. Every outlet will be energized on both shore power and battery power.

I will have to manually select the propane option for the refrigerator rather than the automatic mode and even the air conditioner(s) could be run for a few minutes for a lunch stop beside the road.

Having said this, the installation and parts are expensive. During this process, the trailer will also acquire disk brakes.

[hippygypsy]

Ok. So in answer to the question of the solar person designing this system it would be me. And i have no idea what i am doing...luckily i have you all to help.

So the next question is this..

Where is this wiring diagram for the 1976 trade wind. I would love to see it.

It will seem a lot more practical to wire the outlets in the RV directly to the inverter, since i prefer them to be off of the solar batteries than to rely on shore power. I plan on doing a LOT of boon docking.

I have a Dometic fridge that runs off of propane and electric, and a Girard instahot heater that runs off of propane.

the only major appliance i am looking at for the inverter would be the fridge (sometimes) and the TV when it is on...

I have not found any 12voit tv's with the USB movie player and the built in Wifi. So the Samsung is a good price at the costco...so it is the winner.

Thanks for the advice regarding the batteries...sound like that is what i will be doing with 2 golf batteries from the costco...

I am planning my first small voyage this week and when i reach my friends house i will be completing my floors and my solar system.

We have

2 144w panels
1 30 w MPPT charge controller
1 1000w passthrough inverter
2 6 volt interstate costco golf Cart Batteries.
30 ft of 10g cable
a ton of pure patience
and pic when done.

did i miss anything???

[gandttimes]

A battery monitor,such as the Trimetric TM 2025RV or the newer TM 2030RV so you can really see what your batteries are up to. See " Bob's Solar Blog" for reasons why.
GM

[switz]

This link to a solar system primer might be of interest in filling in any knowledge gaps:

AM Solar's Educational Pages for RV Solar Systems