12K Btu 120V Mini Splits

[jap42]

Las Vegas is mostly dry, the Mojave desert is, just as Death Valley, the dryest place in the US. I grew up with swamp coolers, evaporative coolers, which add humidity as a process to cool the air. Here it works to about 25%, before it looses it's cooling effect. Heat pumps don't  cool enough in the hot summer, heat exchanging doesn't do well when it so hot. I just removed my front roof top Penguin that was 11.5Kbtu  and got a 15K to handle the big windshields.
     Nick what do you think about regional AC issues? lvmci...

I think I am missing your point. As a few others have said which confuses me. Are you saying you dont think a mini split works as well as a roof air?

A mini split works exactly the same as a roof air, except the Evaporator and Condenser are separated. My 12K btu mini will always out preform a roof air for a couple reasons:

First, the compressor is inverter powered, meaning it can change its output. So I get a continuous steady cooling, rather then constant cycling on and off. That means less temperature swing and better recovery.

Second, My condenser is 2-3 times the size of a roof air and has a much higher powered airflow fan. That means it can shed more heat off So it can handle a larger temperature swing.

Swamp coolers do the same thing as a A/C, they cool the air. An A/C moves the heat somewhere else, a swamp cooler converts heat into humidity. An A/C can move heat in any conditions. Its ability is limited only by the size of the components. A swamp cooler only works when there is little to no humidity in the air.

If Jim gets his OTR setup with an electrical secondary he will be styling, that condenser will handle any climate. Reefer units dont have as much condenser. lol

[luvrbus]

I don't think the mini ductless move as much air as roof top the Coleman are 320 CFM but they blow colder air on the low speed ,out here mother nature gives you a lot of BTU's you have to over power with BTU's and insulation .Right now here at 10:30 am we are 102F with 9% humidity perfect for the  evap cooler  in my shop ,the reason AZ doesn't do the daylight saving BS is we don't need more sunshine later in the day

[peterbylt]

I originally installed a 12,000 BTU Pioneer Minisplit, with the Condenser in the front drivers side Luggage Bay and the evaporator over the windshield.

I have been extremely pleased with the result, given enough time the single unit will cool the bus nicely.

The problems come when you want to cool the bus down quickly, living in Florida we also have issue when the temps start to get into the upper 90’s.

In my original plans I planned to install a second 12,000 BTU Minisplit in the back with the evaporator on the rear wall over the bed and the Condenser installed in the engine compartment where I had  removed the original MCI Blackwater tank.

Reality struck and I realized I could not install the Condenser in that area.

Neither me or the Wife really wanted to put an air Conditioner on the roof, After much thought and debate, We decided we would rather be cool, and the decision was made to install a Coleman 15,000 BTU Mach 15 roof top AC in the rear Escape hatch.
 
I wanted to leave my options open and be able change at a future time so, I had my fabricator friend build me a new hatch out of aluminum with the 14” square hole already cut into it, removed and saved the original hatch and mounted the AC in the new hatch.

So far we are very happy with the result, the best of both worlds, We can run both roof top and mini split and cool the bus down instantly, once the bus is cool we shut off the Coleman and maintain with the mini split.

With minimal power we can run the Mini Split only, We can also run both Roof top and Mini Split under full load at less than 25 Amp, Need almost 30 amps to run both AC’s, refrigerator, Hot water heater, TV and house battery charger, need to shut off the Roof Top to run the Micro wave.

No issues at 50 amp.

Peter

[DoubleEagle]

This is going to sound like overkill (cooling wise), but my Model 15 Eagle came equipped with four CruiseAir basement types, and three roof airs, and two generators to make sure they had power. The reason why it was equipped from new like that was because it was for two dozen rodeo riders and crew that traveled all over the west. Looks like they wanted to make dam sure they were cool. Nowadays, they would probably have put in inverter splits down below, but still put roof tops on. The name of the bus was "Rodeo Rose II".

[chessie4905]

Go to any big city and see new entainer coaches parked for performances with 5 or 6 rooftop units. Those people know what works. Btw, ear plugs are cheap. Instead, come up with ideas to make them quieter. Those tall top sides hide them well along with outside noise. Didn't know they actually on awnings. The earlier versions looked too far in to be awnings. Maybe some type of sound absorbant on inside of ceiling cover can work.
Has anyone been using the heat pump versions rooftops? Are they worth the added expense?

[luvrbus]

Go to any big city and see new entainer coaches parked for performances with 5 or 6 rooftop units. Those people know what works. Btw, ear plugs are cheap. Instead, come up with ideas to make them quieter. Those tall top sides hide them well along with outside noise. Didn't know they actually on awnings. The earlier versions looked too far in to be awnings. Maybe some type of sound absorbant on inside of ceiling cover can work.
Has anyone been using the heat pump versions rooftops? Are they worth the added expense?

On my Country coach the faring and awning on the roof you don't see the AC's ,the way mine are ducted and filtered you don't hear them only on the outside,and my heat pumps on the 15,000 Coleman worked like a champ when bring it home across New Mexico 

[lvmci]

   Heat pumps don't cool to the degree traditional AC does, when in temperatures that happen in the desert southwest.Today in LV, 108° with 5% humidity.
   A swamp cooler would cool well, I used it A lot, under the right humidity. i had a house with a piggy back AC/swamper, in my opinion, with the cost savings, this is the best combination...

[luvrbus]

I originally installed a 12,000 BTU Pioneer Minisplit, with the Condenser in the front drivers side Luggage Bay and the evaporator over the windshield.

I have been extremely pleased with the result, given enough time the single unit will cool the bus nicely.

The problems come when you want to cool the bus down quickly, living in Florida we also have issue when the temps start to get into the upper 90’s.

In my original plans I planned to install a second 12,000 BTU Minisplit in the back with the evaporator on the rear wall over the bed and the Condenser installed in the engine compartment where I had  removed the original MCI Blackwater tank.

Reality struck and I realized I could not install the Condenser in that area.

Neither me or the Wife really wanted to put an air Conditioner on the roof, After much thought and debate, We decided we would rather be cool, and the decision was made to install a Coleman 15,000 BTU Mach 15 roof top AC in the rear Escape hatch.
 
I wanted to leave my options open and be able change at a future time so, I had my fabricator friend build me a new hatch out of aluminum with the 14” square hole already cut into it, removed and saved the original hatch and mounted the AC in the new hatch.

So far we are very happy with the result, the best of both worlds, We can run both roof top and mini split and cool the bus down instantly, once the bus is cool we shut off the Coleman and maintain with the mini split.

With minimal power we can run the Mini Split only, We can also run both Roof top and Mini Split under full load at less than 25 Amp, Need almost 30 amps to run both AC’s, refrigerator, Hot water heater, TV and house battery charger, need to shut off the Roof Top to run the Micro wave.

No issues at 50 amp.

Peter

Frist person I ever heard say you couldn't make popsicles with a 12,000 btu mini in a bus when it is a 100F ambient outside 

[TomC]

If you want quiet, I took two Penquin roof tops and converted them to basement units-lot of work and engineering. But VERY quiet. Good Luck, TomC

[Lin]

Rooftop AC noise is mostly the result of high air velocity.  Ducting the units and allowing multiple supply vents cuts way down on the air velocity and therefore the noise.

[jap42]

The only reason you will not see a coach builder use any mini split is because they are not meant for mobile use. So they will stick to RV roof airs so they have a warranty. I lived in a 40' Park model for 5 years. It had a ducted 12K btu roof air. It would cool the camper alright, but you could not hear yourself think it was so loud. I checked out some of the newer ones which were quieter but still quite a bit of noise.

I dont have a CFM spec on these ones but I would say 200-300 CFM. My heat pump in my house is a mitibuiti 24K and that will put out over 500CFM on high. The lack of ducting means less turbulence and less air noise. But plenty of air flow. Higher air flow can help but mostly with dehumidification, Higher airflow can make it seem cooler because your likely to be in the path of cooled air, but to actually drop the ambient temp it would not make a difference. That is completely up to to amount of heat the evaporator can remove.

If we are talking efficiency, yes the swamp cooler is much more efficient, there is no compressor, just fans and a small water pump. But if we are talking effectiveness they are about the same. Its all about the BTU the system is designed to handle. A swamp cooler requires almost twice the physical space for the same BTU and is only effective if the humidity is right. An A/C with a properly sized condenser for the temperature differential is completely effective. The biggest complaint I see from those that have them is finding space to put the condenser.

I am thinking of modifying mine to lay the condenser face down so the fan blows down. Then I will open vent holes below just like the OTR system. We will see what happens with the OTR system. If that craps out I will strip the space out and build my own system that can run off 220VAC or 24-48VDC. One of the thoughts I have about the OTR system is it was built to combat not only the outside temperature but also 47 heaters in the seats. Without all that body heat I think the system can be downsized. 24K seems to cool well. I think 36K will do OTR. One condenser in the old A/C compartment feeding a 24K in the front and 12K in the back. If I did not have the rest of the conversion to do I would put a lot more money into this.

TLDR; My 2X 12K BTU units work great, I could not be happier with the performance. I can not wait to test on the road.

[lostagain]

TLDR means??

[jap42]

To Long, Dident Read. Basically the readers digest version of my endless rambling.

[DoubleEagle]

If you want quiet, I took two Penquin roof tops and converted them to basement units-lot of work and engineering. But VERY quiet. Good Luck, TomC

Tom, I would like more details and pictures when you have time. I have three spare Penguins that need something to do. I have often thought it would be possible, but the details are numerous.

[luvrbus]

Tom, I would like more details and pictures when you have time. I have three spare Penguins that need something to do. I have often thought it would be possible, but the details are numerous.,

Walter you need the ducted version to do that with,the 12,500 and 15,000 Penguins are the same unit if you have 12.500 you just change the blower motor for 15,000 BTU I just did that on mine in the Trek,the new Penguins ll are really junk