4000 Watt Holiday Rambler Class A Build

[Bobert]

There’s 20 panels in the photos so how does that work?

Actually there are 12 in the picture of the present setup ( the monocrystaline panels) they are mounted tight to each other so the separation is not easy to see in the picture. Only a small bead of caulk separates each panels. The original setup had 10 and one panel was wired directly to a separate controller for the 12v house battery.

 

[djnorth]

Boberts RV is the second set of RV pictures starting at post #46. That is who you are asking.

No, I was asking Off Gridin’ It

 

[Off Gridin' It]

But it's a dry heat right?

I wonder about using one of those portable 100v AC units on a 3K system overnight, over here where it's not so hot, but humid .

I use one of the portable AC air conditioners in my small camper. It runs on 120 volt and pulls 700 watts continuous. My camper is only 21ft and it does a pretty good job.

 

[Off Gridin' It]

My trailer is a 38’ (35’ box) year 2000 keystone Springdale. A very similar layout is still made today. I originally mounted 10 240 watt panels on my roof. I used brackets that I made using extruded aluminum channel that was recycled from bleachers that were thrown away from our local school. I used a chop saw (with some difficulty) to cut the Essentially long aluminum “angle iron” into short brackets and By bolting two of these brackets together I was able to raise the panels 8” above the roof so all of the vent fans can open. Initially I left a space for the rooftop ac intending to eventually install 2 more panels and remove the rooftop ac and install a mini split. Several months later a storm came through where we were camping and sent a good sized poplar tree tumbling down on the camper roof. Since buying 12. 270 watt panels locally was cheaper than replacing the 3 broken 240s I decided to bite the bullet and put in a mini split and covered the roof with 12 panels giving me a nominal total of 3240 watts. I still have a 14” path on the left side of the roof where I can clean the slides and the solar panels. I had to create an airfoil as the front panels would have been susceptible to lifting from the wind. I also put on “skirting “ on the driver’s side to hide the brackets. My battery is a 5k lifepo4 made from four 100ah 12volt batteries in series they are connected to a 3500w Powmr AIO. I use a separate lifepo4 100ah battery for my 12volt system and that gives me some redundancy.

I think I would be sick if that happened!! Ugh!

 

[Off Gridin' It]

I’m referring to the OP of the RV. Upon closer inspection there appears to be 10 panels with each panel appears to have 2 PV cell arrays, so 10 400W panels?

Yes, it is (10) 400 watt BYD panels. Wired in 5S2P for a total array spec of 246.05 volts and 19.58 amps.

 

[Bobert]

I think I would be sick if that happened!! Ugh!

Actually it was quite a blessing that the solar was there. I had just gotten inside the trailer when the storm hit the camper was the only form of shelter close enough to reach when I heard the trees crashing down in the forest and saw the fireworks from the power lines about a tenth of a mile from us. I’m pretty sure if the array had not softened the impact of the tree it would have come through the roof of the travel trailer and possibly injured me. As it was I was able to patch the roof in a few hours and reconfigure the wires to get us back to 2/3rds capacity. Within a month we were up and running with Almost 1000 watts more solar than the original array and a mini split just In time for some of the muggiest summer weather we have had in years. It all turned out very well. We never even had to quit camping.

 

[Off Gridin' It]

Actually it was quite a blessing that the solar was there. I had just gotten inside the trailer when the storm hit the camper was the only form of shelter close enough to reach when I heard the trees crashing down in the forest and saw the fireworks from the power lines about a tenth of a mile from us. I’m pretty sure if the array had not softened the impact of the tree it would have come through the roof of the travel trailer and possibly injured me. As it was I was able to patch the roof in a few hours and reconfigure the wires to get us back to 2/3rds capacity. Within a month we were up and running with Almost 1000 watts more solar than the original array and a mini split just In time for some of the muggiest summer weather we have had in years. It all turned out very well. We never even had to quit camping.

A positive outlook like that is great!

 

[ArtDeco]

I use one of the portable AC air conditioners in my small camper. It runs on 120 volt and pulls 700 watts continuous. My camper is only 21ft and it does a pretty good job.

Cool. Does it have a big start up draw ?

 

[ArtDeco]

They’re standard on pretty much all RVs.

Actually the three way refrigerators standard on small rvs are all absorption, no compressor IIRC.

 

[MrThisIsME]

Actually the three way refrigerators standard on small rvs are all absorption, no compressor IIRC.

Correct, most are 2-ways (AC & gas). I think the OP was mistaken when he said propane and compressor in one unit. I cannot find one. Asked my old-timer RV dealer and never heard of such. There might be.....who knows.
Only time you see a compressor unit on an RV is then they have a "Residential fridge". I had such option on my RV, but declined it. In hindsight I mind do different. Absorption fridges are terribly inefficient on AC

 

[ArtDeco]

Absorption fridges are terribly inefficient on AC and on 12 volt DC and on propane ... and none of them can freeze a tray of ice cubes
So inefficient cubed , I guess.
Like

 

[MrThisIsME]

Absorption fridges are terribly inefficient
Like

No they are not. Go to your local grocery store, all absorption.

and none of them can freeze a tray of ice cubes

Like

I have been making cubes in mine for over 5 years no problem. Matter of fact, never seen one that could not. Not sure where you are getting your info from.

Still looking for that propane / compressor fridge you said was in RVs. I am definitely interested.

 

[ArtDeco]

I said the 3 way absorption fridges usually standard in small rvs are inefficient all three ways and won't freeze an ice cube. That`s not just my experience, it`s pretty well known among campers and boaters. The compression refrigerators that I`ve seen in RVs are not 3 way units. Three ways mean propane/12 volt/ or 110 volt and they are not compressor driven. IDK about grocery stores. Or anything about their efficiency (BTU per watt?), the joke should have been ineffective cubed. I think you will look for that propane compressor refrigerator as long as you will for a propane powered microwave.

 

[MrThisIsME]

I said the 3 way absorption fridges usually standard in small rvs

2 way fridges are standard, not 3 way.

That`s not just my experience, it`s pretty well known among campers and boaters.

I am on my 5th RV and all all 2-way fridges made ice no problem on the lowest of three settings.

Three ways mean propane/12 volt/ or 110 volt and they are not compressor driven.

You previously stated a propane fridge with a compressor was the standard on RVs.

IDK about grocery stores.

Obviously, as they use absorption because it is so efficient.

 

[ArtDeco]

As above. I asked the op if the unit had a compressor fridge, induction cooktop, etc.

 

[sunshine_eggo]

No they are not. Go to your local grocery store, all absorption.

Walmart doesn't. Fry's Doesn't. Safeway doesn't. Albertson's doesn't. The grocery store I worked in in 1986 didn't.

The ones in RVs are inefficient as hell. They use 5-6X the AC power of that of an efficient vapor compression fridge. Many new RV units aren't even bothering with absorption and include compressor fridges with small dedicated inverters.

Absorption refrigerator - Wikipedia

en.wikipedia.org

low coefficient of performance (about one fifth of that of the vapor compression cycle). Absorption refrigerators are a popular alternative to regular compressor refrigerators where electricity is unreliable, costly, or unavailable, where noise from the compressor is problematic, or where surplus heat is available (e.g., from turbine exhausts or industrial processes, or from solar plants).

I power my double door Norcold on AC power, and it consumes about 8kWh/day running 450W about 18 out of 24 hours in 68-90°F ambient conditions. A similarly sized residential unit would use about 1.5kWh/day.

I have been making cubes in mine for over 5 years no problem. Matter of fact, never seen one that could not. Not sure where you are getting your info from.

Too often, short timers are not turning them on 12+ hours in advance, AND they load them up with a mix of refrigerated and unrefrigerated items. It can take 24-48hours of near full running to get to temp. Additionally, many RV installations are marginal further inhibiting performance. Eventually, they freeze fine.

Both sides of my double wide sit at about 0°F pretty consistently on setting 3 of 9. The fridge portion struggles to maintain 40°F. I've improved the cooling baffling and added supplemental fans to the condenser, and it didn't make much difference.

Still looking for that propane / compressor fridge you said was in RVs. I am definitely interested.

No such beast. The refrigeration equivalent of a snipe hunt or a jackalope.

Again, I can't stress it enough, RV fridges are VERY inefficient. Propane is just a very energy dense storage medium, and it makes sense vs. trying to produce enough AC to power a residential fridge while boondocking.

EDIT:

here's the last 24 hours of use:


Opened ZERO times for the last two weeks.

 

[MrThisIsME]

Walmart doesn't. Fry's Doesn't. Safeway doesn't. Albertson's doesn't. The grocery store I worked in in 1986 didn't.

Strange. Cousin is an HVAC guy that contracts with all the Walmarts locally and a few other Grocery stores - he would beg to differ.

No such beast. The refrigeration equivalent of a snipe hunt or a jackalope.

I never said there was. The person I responded to claimed there was such a beast. I would love to see a propane / compressor type fridge.

I power my double door Norcold on AC power, and it consumes about 8kWh/day running 450W about 18 out of 24 hours in 68-90°F ambient conditions. A similarly sized residential unit would use about 1.5kWh/day.

Agree. This is the struggle I have and your numbers match mine. Mine is a 16 cft and I see 450w same as you. I cannot make out your timeline in your graph, but mine is about 85 - 90% (seat of the pants) at 450W. But by your own statement it is not efficient on AC, but efficient on propane. I had the option to check a box for a residential compressor type fridge and have been kicking myself. Than again it is nice to be able to fall back on the propane.

The ones in RVs are inefficient as hell.

They were designed and conceived to run on propane which they are very efficient. At the design time it was assumed that if AC was required you would be on shore power. Times have changed.

 

[Bobert]

Absorption fridges are terribly inefficient on AC and on 12 volt DC and on propane ... and none of them can freeze a tray of ice cubes
So inefficient cubed , I guess.
Like

I have noticed that many of the absorption fridges are improperly installed from the factory and that makes them run hot.

 

[sunshine_eggo]

Strange. Cousin is an HVAC guy that contracts with all the Walmarts locally and a few other Grocery stores - he would beg to differ.

Not sure where your cousin is. Why would any business choose to quintuple their energy cost? The only time absorption systems really make sense is if you need a MASSIVE system as they are much more scalable than compressor type. Maybe that's required of the big walk-in freezers in the back, but not on the floor refrigeration units.

I never said there was. The person I responded to claimed there was such a beast. I would love to see a propane / compressor type fridge.

I was just reinforcing.

Agree. This is the struggle I have and your numbers match mine. Mine is a 16 cft and I see 450w same as you. I cannot make out your timeline in your graph, but mine is about 85 - 90% (seat of the pants) at 450W. But by your own statement it is not efficient on AC, but efficient on propane. I had the option to check a box for a residential compressor type fridge and have been kicking myself. Than again it is nice to be able to fall back on the propane.

That chart is for a 24 hour period.

Important to define efficiency:

Efficiency: "the ratio of the useful work performed by a machine or in a process to the total energy expended or heat taken in."

They are no more efficient on propane than they are on AC. 8kWh is about 27,000 BTU. It will take that much from propane as well. That's why 30# bottles typically last about 3-ish weeks.

They were designed and conceived to run on propane which they are very efficient. At the design time it was assumed that if AC was required you would be on shore power. Times have changed.

Propane is a more efficient energy storage medium than batteries from a mass and volume perspective, but the fridge is not more efficient on fire than it is on a heated element, i.e., it takes a given amount of heat energy to operate as a fridge, regardless if that heat comes from electricity or propane.

 

[ArtDeco]

I have noticed that many of the absorption fridges are improperly installed from the factory and that makes them run hot.

Very possible. We have a lot of Mennonite and Amish that use propane refrigerators full time. But they aren't banged around at 60 mph either.