Reasonable Window A/C? ($129, 11.1 EER, 5k BTU, 336/400 Watts)

[itsmeagain]

Still on my never ending journey to spec out a reasonably priced window a/c that can be run on a solar system capable of being mounted on a van..  probably on my third year of lurking, reading, and paying rent.

I'm stuck in South FL due to my job, and I can't leave for a cooler place. The environment is just "urban" enough that a generator is a noise issue.
I love the super efficient ~33 SEER a/c unit Jim Ragsdale posted.. but that price point is out of my range.

I spotted this 5k BTU unit on Amazon for $129 with an EER of 11.1. According to this guy's review, "High" setting with compressor is 336 watts, and the startup surge is 400watts:
https://www.amazon.com/Frigidaire-FFRA0511R1-Window-Mounted-Mini-Compact-Conditioner/dp/B00W2KG92Y/

[font=verdana, arial, helvetica, sans-serif]So here are the four readings for you. I used a devise called a Wattsup Pro to measure. This device is an inline power monitor. Fan only Low 57.2 Watts, Fan Only High 60.3 Watts, Low cool w/ compressor 324 Watts and surprisingly High cool w/ compressor 336 Watts. So what that tells me is the fan low versus high shunts some of the power through a resister. Very little difference between low and high 3Watts Fan and 12Watts difference with the compressor. I will likely no longer run the unit on low to save energy again. Hope this helps. FYI during start up is did reach about 400 Watts on the meter. Not really the inrush power but gives you some idea of start up demand if you are planning a generator to run the unit. This is likely far more info than you needed. The unit also has what looks like a GFI plug with resets. It could just be a circuit protector.[/font]

Would two 300watt panels, mppt controller, 4 6V GC batteries, and a 1000watt pure sine wave converter be able to comfortably handle this without destroying the batteries?
Still not even sure I could fit two 300watt panels on my promaster city, but I'll do anything for solar A/C at a reasonable price at this point.

Unfortunately my situation prevents me from re-locating to a cooler climate, nor can I run a generator everyday for extended periods. 
I've got to figure this out.. and the silver lining is, the longer its taking me to figure this out, the cheaper and more realistic it's getting.

Any input is greatly appreciated. Thanks!

 

[highdesertranger]

Thread moved to Forum's Trash Can to retain record of member(s) behavior(s).

 

[itsmeagain]

highdesertranger is a nice guy =)
He fixed my post. Thanks!

 

[John61CT]

No, absolutely not enough, really just not practical IMO, rich man's overlander toy sort of project.

Running **any** A/C more than a few minutes per day will require thousands of dollars of infrastructure, no way less than a kW of panels.

You're talking about 30+A running pretty continuously while on, say ten hours a day is ~300AH, so 1200AH would IMO be the minimum bank size, 2kW panels even if in strong sun every day. Double that for 15-20 hours a day.

Better to get a place to park with mains power, use a very quiet genny, or acclimate to get by with ventilation only.

 

[jimindenver]

That is so funny.

Yes 600w of panel will run a 336 watt load on a peak sunny day. I use 750 watts to run mine pulling 450 watts all the time. Now running it at night too and expecting to recharge the loss to the batteries while running at peak during the day on 600 watts of panel is too much to ask for.

You mentioned 300 watt panels. I would suggest looking for the highest wattage you can find in the same footprint, that would be 340 watts per panel I believe. Also all inverters are not equal. I use a industrial MSW inverter because it is designed to take the punch of starting a motor.

 

[jimindenver]

I wanted to add that this is the lowest draw A/C they put out with a EER of 12.2.

https://www.amazon.com/dp/B01B4XUUDI/ref=psdc_13397451_t3_B00W2KG92Y

 

[itsmeagain]

I figured it would either be un-doable, as John61CT said, or only able to run when the sun is in the perfect position, as jimindenver posted as well.
Actually, a lot of jimindenver's A/C posts give me hope that I could pull this off one day.

I'll look into those 340 watt panels and the more efficient window AC, but now is about when the hesitation sets in and I start thinking there's no way I'll be happy after doing all that, and not being able to sleep comfortably. Although, it'll certainly help during the scorching days when the sun is at high noon.

I dunno.. maybe the time still isn't right. =/

 

[John61CT]

I figured it would either be un-doable, as John61CT said

No, just not for cheap. And the more you try to save up-front the more you'll spend over time.

Do it right with quality gear, you can probably get the average cost down to say $300-400 per year.

Note that'll end up no more expensive than B&S, maybe even cheaper over ten years as mains electricity kWh pricing goes up.

 

[itsmeagain]

No, just not for cheap. And the more you try to save up-front the more you'll spend over time.

Do it right with quality gear, you can probably get the average cost down to say $300-400 per year.

Note that'll end up no more expensive than B&S, maybe even cheaper over ten years as mains electricity kWh pricing goes up.

Right.. I understood that the budget is the deal killer.
Also, the roofspace is probably a deal killer is as well.

Not sure if it's even physically possible to get 1kw above a Promaster City, even with a bumper to bumper roof rack like this: 

[img=320x240]https://s-media-cache-ak0.pinimg.com/originals/ec/d3/85/ecd385e63b984046ddc66010358e9c05.jpg[/img]

 

[akrvbob]

If you had a Promaster instead of a Promaster City I'd say you could easily get 750 watts on it and that would easily make solar very practical. But on a City it just isn't realistic.

The key is how much do you want to run the AC and how much can you manage it? My suggestion is to super-insulate the van R-12 in the Walls and R-18 on the roof and run the AC 20-30 minutes an hour or less. I think you could do it with a Promaster City if you can get 500-600 watts on it. But you have so little space and loosing 2 inches off all the walls and 3 inches off the roof would be a hardship

 

[itsmeagain]

If you had a Promaster instead of a Promaster City I'd say you could easily get 750 watts on it and that would easily make solar very practical. But on a City it just isn't realistic.

The key is how much do you want to run the AC and how much can you manage it? My suggestion is to super-insulate the van R-12 in the Walls and R-18 on the roof and run the AC 20-30 minutes an hour or less. I think you could do it with a Promaster City if you can get 500-600 watts on it. But you have so little space and loosing 2 inches off all the walls and 3 inches off the roof would be a hardship

Thanks Bob!!
Yes the hard truth is I'll need to swap for the fullsize promaster to do this the right way.
In fact, I wanted the High Roof Extended wheelbase model before I got the City, but had to keep the vehicle garage-able due to my job.

 

[tx2sturgis]

Jim, John, Stern, Bob, Richard, and others....I wonder if we could come up with a very basic chart for this dilemma. It comes up over and over again.....I bet someone can figure out the formulas and get some basic, 'ballpark' estimates together.

Something like a chart with square footage of panels and wattage, vs climate, vs battery size, vs BTU needed.

There would probably need to be a correction factor for well insulated or not, and hours of use per day, etc.

We've all seen charts like this, but I haven't seen one for mobile AC use on solar...if someone has aggregated the data in one place, I have not seen it.

Start with what we know CAN work, what we know WONT work, and fill in the chart from there.

Parameters could be adjusted for location, season, etc.

Lets say, the lines in the chart cross at point 5b, for instance, and they move from SD to FL, they might need to look at the figures in line 7d, or whatever...

The chart would be updatable as changes in technology move this whole idea from 'impossibly expensive' for a van dweller or RVer to 'reasonably affordable'.

As the OP pointed out, advances are being made in batteries, solar panels, and AC units.

Does any of this sound doable?

:huh:

 

[highdesertranger]

how can I be diplomatic about this.

the way I get around not having an AC in my living quarters is I am not inside the vehicle during the hot part of the day. plus I try to stay away from areas that have high night time temps. now I realize that for whatever reason not everyone can do that but that is how I deal with it. no AC makes life much simpler and much greener.

was I diplomatic? highdesertranger

 

[tx2sturgis]

HDR, we think alot alike in that regard, but the trucking industry has some effective (but expensive) solutions for climate control when parked in anti-idling zones...I wonder if there might someday be something similar for RVs, vans, trailers, whatever.

I have about 20 years experience with class-8 OTR tractor APU's, and if someone could figure out a way to downsize these for recreational use, I think they could make some money.

 

[jonsun]

1000w inverter lol. You'll need a couple big ol hard start kits.

Think more like 2500w...an AC's surge wattage is huge

 

[jonsun]

I mean lets put it in perspective...a single roof top 13.5k btu unit struggles hard on a 26-28ft RV in the sun. that's why most RV's have at least 2 for 27k btu. 5k btu is miniscule.

You're going to spend thousands so you can park in the direct sun at the hottest part of the day in order to run a tiny little AC part time and likely not even break even.

Just save yourself the hassle and get a $250 generator and make a quiet box for it. Then run an AC that will actually be effective.

 

[itsmeagain]

1000w inverter lol. You'll need a couple big ol hard start kits.

Think more like 2500w...an AC's surge wattage is huge

The review used a kill-a-watt type device and measured surge wattage to be 400.


I've read more than a few posts of vandwellers using a 5k btu a/c hooked to a generator to adequately cool their van.
Understandably, I would able to use it for far less stretches of time, in direct sunlight, at high-noon, etc..  so your point is still valid.

I also agree, as it is right now with current technology, it wouldn't be worth dumping thousands into a solution that keeps me comfortable for 2-3 hours of the day.

 

[jonsun]

I have a 10k btu and a 2800w surge generator. It cant handle it.....

that 10k doesnt make a dent in my van...its a portable though and those apparently suck. I got it between the seats and semi-sealed toward the drivers compartment with the heat hose out the passenger window....doesnt make a damn dent at 95f+

 

[itsmeagain]

Maybe it's time to resort to a cool suit, like the kind nascar drivers and astronauts wear.. https://en.wikipedia.org/wiki/Liquid_Cooling_and_Ventilation_Garment


..  i think I'm kidding ...

 

[itsmeagain]

I have a 10k btu and a 2800w surge generator. It cant handle it.....

that 10k doesnt make a dent in my van...its a portable though and those apparently suck.

yes portables defeat the entire purpose.

They remove heat, and then dump it into the same room they removed it from.