mini split air conditioners

[peterbylt]

Phuriousgeorge,

The unit I got is the 17 Seer unit.

https://www.highseer.com/high-seer-inverter-mini-split-ductless/ductless-mini-split-heat-pump-wys012a-17.html

I tried to use the Flat rubber mounts that came with the unit, discovered that I needed more height for the condensation drain that I will need when/if I ever run it in heat mode.
The rubber mounts lined up almost perfectly with the high side of the ribs stamped into the Bay Floor.

Lee Bradley,

Thank You for the suggestion to use two drains for the condensation drain on the inside unit, I have not addressed a permanent solution for it yet, currently I stick the tube out the driver's window, I plan to replace that flimsy tube they give you with some PEX tubing.
 
The Mounts on it now keep it mounted pretty solid, I will investigate mounting it from the top as well.

I also plan on creating a shroud on the exhaust side out of solid foam insulation board to channel the hot air out the hole I made into the OTR Air Bay, that should keep the exhaust out of the intake side.

luvrbus,

I have not used it in temperature's that hot (yet) so I cannot say if it will shut down, I hope not, The wife would have us camping in a Holiday Inn, or idling the bus to run the OTR air.
 
Possibly try a misting device like some Busnuts use on their Radiators?

Tom Y,

Sure I would like to take a look, do you have any pictures? Probably won't be a good match for the 96A3 bay doors.

My current plan is to take off the lower Bumper looking part and recreate the look with expanded metal just like they did on the OTR Air bay door, I want to keep the upper stainless part and the door latch intact.
 
Hoping that will allow enough airflow to operate the AC and/or the generator. (once I get the Generator operational)



Peter

[Lee Bradley]

    This is very useful info, Lee, thank you.  Do you have the brand name and model number for the transformer handy?  I am very interested in going this way.   Thanks!!   Bruce H

It is a PYLE PVTC5000U

[Oonrahnjay]

It is a PYLE PVTC5000U 

    Thank you, Lee.  That's very helpful.  Do you know if it's practical/possible to "hard-wire" the 240V output of that unit?

[Lee Bradley]

Just about anything is possible. You could take the case apart and drill it for conduit and hard wire it.

[brmax]

I dont mind anyone continuing an old but good thread topic, besides the title is spot on.
Anyway do some of you recall someone doing or considering the instalation on these condensors at the top rear of the coach. This was mentioned in a build conversion or major retrofit kinda reno.
I found this pretty interesting and knowing its a major project separating this new area from the inside and for-sure considering the weather and its influence in the area.


Hey just rambling the ideas

Floyd

[Tom Y]

Peter, I found my condenser door. All mesh, looks like yours but 30" H, 34" W.

[Aviator]

Hi Guys

Late to the thread but I have a minisplit installation I'm pretty happy with

I put my outdoor unit in the old condenser bay.  I made a unistrut structure, and put grating at the bottom to admit air from the bottom  Exhausts hot air out fo the side.

Inside I used 3 of the Ducted version of the inside unit. placed them behind the closets and used the back of the closet as the ducts  Water drains through the floor and bay to outside

For power  mine is a 220V unit and i have a step up transformer  pulls less than 25 amps at 110V when the AC is running full tilt.  I run it off the inverter going down the road with the inverter pulling 24VDC from the bus alternator.  My OTR AC is disabled but I use the coach heat in the winter

Larry 102C3 Cummins L10-30

[Oonrahnjay]

Hi Guys
Late to the thread but I have a minisplit installation I'm pretty happy with ... Inside I used 3 of the Ducted version of the inside unit... For power  mine is a 220V unit and i have a step up transformer  pulls less than 25 amps at 110V when the AC is running full tilt ... 

    Hi, Larry.  Welcome to the Forum - you'll find a wealth of information and all the opinions you could ever use.  There is tremendous experience and background among the members here.  I could never have navigated this bus ownership mess without the help here.

   What's the make and model of the unit you're using, also, what transformer?  I need at least two inside (evap) units.  I sat down last night and spec'd a Daikin system with a 48K BTU central unit, two horizontal inside evap units, and a 2'-square ceiling mount unit.  It looks good but Daikin calls for a power draw of 40A @ 240V (about 9600 watts); the 36K BTU unit is only about 15% less amperage draw and, considering my unusual needs, I'm worried that that won't be enough. 

[Tom Y]

Larry what L10 are you running? Electronic? Thanks Tom

[Lee Bradley]

   What's the make and model of the unit you're using, also, what transformer?  I need at least two inside (evap) units.  I sat down last night and spec'd a Daikin system with a 48K BTU central unit, two horizontal inside evap units, and a 2'-square ceiling mount unit.  It looks good but Daikin calls for a power draw of 40A @ 240V (about 9600 watts); the 36K BTU unit is only about 15% less amperage draw and, considering my unusual needs, I'm worried that that won't be enough. 

I don't know that a transformer is going to help. With that load, what are you going to feed the transformer with? That is over twice the output of most inverters you will see in RVs and the battery bank to operate it would be impressive. That is more the full output of the big gear driven bus alternators 28 volts x 270 amps is 7560 watts.  Maybe a 240 vac diesel generator.

[Oonrahnjay]

... I don't know that a transformer is going to help. With that load, what are you going to feed the transformer with? That is over twice the output of most inverters you will see in RVs and the battery bank to operate it would be impressive. That is more the full output of the big gear driven bus alternators 28 volts x 270 amps is 7560 watts.  Maybe a 240 vac diesel generator. 

      I have a 10K diesel Onan but I wouldn't think of trying to run it almost full time at 96% of its rated capacity and expect it to perform well and last.  I put that example up to show what the first little bit of my research pulled up.  I (think I) remember Clifford saying that a coach needs to have about 48K BTU (or 4 12K BTU rooftops) to assure reasonable pull down and reliable comfort in his Arizona climate and I think that I should be sure that I have cooling at about that level.   Still, my goal is to find a system that's much more in the range of Larry's current draw but still meets my needs (don't forget, I have two levels - upstairs and downstairs - to deal with).  But Daikin's tech data was very vague about the real-life total draw of the 48K "outside" unit and also two or three inside units so I'm not sure exactly what would be required in real life. 

      On a completely different tack, Mr. Welch at Welch A/C in Georgia suggested a big "dash" A/C unit driven off an engine driven compressor for traveling and driver/copilot comfort and a moderately big mini-split upstairs for cooling when parked (bedroom, living room, toilet/bath are all upstairs).   One issue is bedroom is in the rear and it might be necessary to have a separate inside unit for good cooling, resulting in two units upstairs driven by a single compressor mini-split unit and that would almost certainly put me in the 240V system category.

     Thanks for info, Lee.  I'm going to keep looking and considering what would work best for me. 

[TomC]

Insulation is the key-I have 2.25" of spray foam insulation and have 3-13,500btu roof tops, of which I usually only need two.
A couple of observations from pictures of installations. You must make an effort to keep from the hot exhaust air mixing from the cool air coming into the condenser. Many of the pictures just show the unit sitting in the bay-should have sheet metal around the unit to keep the two sides (hot and cold) from mixing air.
Also, with the picture of the freon lines, the return line to the condenser should be insulation wrapped. You'll get a noticeable increase in cooling if the return lines are wrapped. Good Luck, TomC

[sledhead]

this was on the M C I . the green round thing is a 10" inline fan that pulls air through the system from the old bus a/c bay through a filter then through the a/c unit and out . I set the fan speed on a fan dimmer so I could control the speed and sound when parked . used it with my inverter when on the road as well , all worked great

https://photos.google.com/share/AF1QipNFw14Ggy267sHvvAcBBp6Ne-XYPEKJxJY0csKJywHnvVWwwM4o0aERxPYJzBVhfw/photo/AF1QipNRZ9sMztjJdy05nKWvUACvuCkdQRt0uBZqWLvY?key=VFN3RFRCbktmRHlKTlVkZU1haTk3aFpLcWljYi1n

https://photos.google.com/share/AF1QipNFw14Ggy267sHvvAcBBp6Ne-XYPEKJxJY0csKJywHnvVWwwM4o0aERxPYJzBVhfw/photo/AF1QipMlp1-xqmhkbnwdKZi_dsHQqf9x6GZwPe68gsvV?key=VFN3RFRCbktmRHlKTlVkZU1haTk3aFpLcWljYi1n

https://photos.google.com/share/AF1QipNFw14Ggy267sHvvAcBBp6Ne-XYPEKJxJY0csKJywHnvVWwwM4o0aERxPYJzBVhfw/photo/AF1QipPIUfzRDfPhPVlk4nUmovnojE0xy5xykk3_CPBJ?key=VFN3RFRCbktmRHlKTlVkZU1haTk3aFpLcWljYi1n


dave

[buswarrior]

Filters must be a consideration for our mobile uses.

Condensers filled with road dirt/small stones, dried leaves, pine needles, bird nests...

Protect your investment, get something in between the great outdoors and your expensive HVAC parts.

Inexpensive solutions can be had, backed up with a bit of cross bracing so they don't collapse underway, or when wet...
Or spend money on purpose designed metal solutions.

And then turn your OCD loose on calculating the air flow obstruction and the upsizing to accomodate....

You're welcome, and I'm sorry?

happy coaching!
buswarrior

[luvrbus]

These AC topics get sorta of funny, I was reading on F/B this guy had a spray foam bus with a 12,000 btu mini,he showed the charts of the outside temp being 87 degrees and how great his split was working it was a cool 77 degrees inside the bus.
I live in AZ yesterday it was 112 he would look like rare prime rib here in a couple of hours with a 12,000 btu unit split or non split