Solar Modification Update

[RollingManCave]

I am currently located in Florida next to the beach doing some writing. I started out the morning after a comfortable evening in the solar powered A/c birth. The little 2800 BTU did not have to work too hard as it had cooled down after the rain storm (From which I collected 20 gallons of water for the storage tank). The little A/C only produced about a 1/3 of a gallon of water for the tank last night. It used about 1/4 of the 280ah battery. I was having problems with the A/C until I discovered the A/C power brick was getting hot. I relocated it on top of a piece of cutting board and attached a USB powered fan to it (problems solved). Anyway, I slapped up the magnetic cab screens and rolled the windows down. Set up the 450 portable solar panel for the battery bank and the 125 watt panel for the coach battery. The roof solar was already plugged into the Solar generator. I settled in with some coffee made from solar power and began to write. A few hours later I noticed it was getting hot inside the MH, as the wind had dropped down to nothing. Back-story I had completed the cab divider I made for the back bedroom/toy hauler area, similar in design to the Bunk and Cab divider. I was still not getting the comfort level out of the new 5000 btu unit that I had placed between the seats in the cab. I could go bigger but that means more watts. I am going to add another divider behind the dinette/kitchen are to make the area even smaller and see if the 5000 btu a/c can keep up. All was not lost, as when I finished the test and rolled the rear divider back up, I noticed the nice cool stream of air coming from the A/c and decided to place a fan in front of it and aimed it at my dinette, where I do my writing. Back to the story at hand, It is now about 130pm and I have the cab divider down with the 5000 btu A/C venting out the Magnetic screens. The big dinette window and kitchen window are open for fresh air and the cool air from the a/c is being directed by the 12 volt fan keeping me cool and comfortable. The Solar generator is showing 900 plus watts comming in and a 400-500 going out. When the breeze picks back up around 3 or 4 pm I will shut the air-conditioner down and raise the divider. I am going to test this out for a week and see how it does. For now, all is cool and going well as not planned.

 

[Kevin D Pem]

I'm impressed!
So if you want to move to a more efficient 5000btu unit you might look into a Midea inverter unit.

 

[RollingManCave]

I'm impressed!
So if you want to move to a more efficient 5000btu unit you might look into a Midea inverter unit.

Thanks, I am checking it out. The price is only $30 bucks more than the A/c I bought. I am not sure I will get more cooling. Both are rated for same BTU and Watts. The amount of air flow may not be the issue, It is the direction. That is why I have a low wattage fan in front of it blowing it in the my direction. If it lasts longer and fits in the same space it may still be worth it after I burn this one out using it as a cooler. Today is the second day of using the A/c as a personal cooler. Cab divider in place and a/c exhaust blowing out the Magnetic Window cab screens. Dinette and kitchen window wide open. Fan in front of a/c blowing towards me. Temps are perfect! Using 460 watts. Today: Life is good for this RV writer. I still plan on reducing the space with another divider. I don't want to go over 500 watts. Time will tell. Thank you for the info.

 

[Kevin D Pem]

They call it a horse shoe case. They have the regular units as well, like those at Walmart. Do your research "inverter drive ".

 

[RollingManCave]

They call it a horse shoe case. They have the regular units as well, like those at Walmart. Do your research "inverter drive ".

I did look at these and they are huge and heavy. It has to fit between the seats and engine well (It's a van front). They say up to 35 % energy savings but still need the same 90 watts per 1000 BTUs off cooling as the other units.. There is no test data or SEERs value listed so they can say anything. The minimum 8000 btu size was their smallest that I could find and that is 710 watts to power it and it's a big pig as well. Research shows they are well made. I would probably have to tear the passenger seat out and turn the a/c into a seat to make it fit. I'll keep looking.

 

[Kevin D Pem]

Have a friend with a small one. Guess not enough people want one that small. He can run it on solar all day long no problem in Quartzsite AZ. I looked for one and did not find it.

When I pull the trigger, I will do the 9000, as it would not ever run full tilt. You know how inverter acts work so you know what I am saying.

 

[Kevin D Pem]

My first personal experience with a VFD, was on a drive I was assembling for my aux Edrive sailing vessel. Not large! The drive was a 3hp 220v electric motor coupled by a VFD using a 2500 watt gasoline powered generator.

You might consider that for a minute. Because a VFD can adjust the ramp up, there is no locked rotor draw to overcome. The rpm can be changed according to demand. Totally adjustable with consistent torque. Basically an inverter whose parameters can be changed according to need.

This with an expansion valve/capillary tube, and a variable speed compressor, are the essence of an inverter A/C unit.

It would be impossible to establish a true ceer number because the numbers constantly change with conditions.

had I not found this unit for 50 bucks, this picture would be sporting the 8000 midea inverter unit. That unit is simply a mini split in a single unit.

An explanation!
What you're looking at is a home grown B.O.T. pod of limited functional space. Built on a harborfreighttools 4x8 trailer bed. Contains a heated bed for cold weather, an A/C unit, standing room for getting dressed, head, comfortable seating, and 1.8 refrigerator. All can be run for a time off 500w of solar.

I am impressed by you because you see the world as your science project! Not something I see often!!

 

[RollingManCave]

My first personal experience with a VFD, was on a drive I was assembling for my aux Edrive sailing vessel. Not large! The drive was a 3hp 220v electric motor coupled by a VFD using a 2500 watt gasoline powered generator.

You might consider that for a minute. Because a VFD can adjust the ramp up, there is no locked rotor draw to overcome. The rpm can be changed according to demand. Totally adjustable with consistent torque. Basically an inverter whose parameters can be changed according to need.

This with an expansion valve/capillary tube, and a variable speed compressor, are the essence of an inverter A/C unit.

It would be impossible to establish a true ceer number because the numbers constantly change with conditions.

had I not found this unit for 50 bucks, this picture would be sporting the 8000 midea inverter unit. That unit is simply a mini split in a single unit.

An explanation!
What you're looking at is a home grown B.O.T. pod of limited functional space. Built on a harborfreighttools 4x8 trailer bed. Contains a heated bed for cold weather, an A/C unit, standing room for getting dressed, head, comfortable seating, and 1.8 refrigerator. All can be run for a time off 500w of solar.

I am impressed by you because you see the world as your science project! Not something I see often!!

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I like it! I did my walls in my Nissan Niv out of the same material. I had thin T&G pine over the top of it on the ceiling. I sold it before I got the walls done. I vented a portable a/c flex tube out the vent behind the wheel wells. I will keep looking at the A/C but I think when I have the area down to 8x8, the 5k unit I have will work. Right now It has been doing fine as a cooler. I have been inventing things since I was a kid. I am not an engineer so I have to build, test, rebuild and repeat. . There used to be lot of people like us before the pencil pushers stopped the imaginative creators with all their laws. Guys like this is what made America great, IMHO: Chris Heintz (aeronautical engineer) - Wikipedia
My guess he hated working on just one piece of an airplane but made a lot of money doing it. He smiled a lot more when he made less money working on the whole plane.