Anyone used mini-split A/Cs in a conversion?

[belfert]

Has anyone used mini-split air conditioners in a conversion?  I think I could fit two of the 1 ton size in my former condensor area.  The 1 ton units are 110 volt.

Would the copper lines end up cracking from vibration and such?

Brian Elfert

[Kristinsgrandpa]

  I bought 2, 12,000 btu mini splits for my coach. Not installed yet.   I'm still working on the 2" of insulation.
Fasten/strap the lines down good.

Ed

[Nick Badame Refrig/ACC]

Brian,

They are a good option when you are able to intergrate them into your walls or layout.

The biggest downfall, you are limited to the location of the condencers. They all vent horrizonally. which, on most occations will eat up your bay space.

We just installed a pair of 12's for Dan Odio in V.A.  and he will need a third one, with not much room left over [CFM wise]

Here's a pic of my stacked basement HP's but, I think I gave you this pic allready!

Nick-

[belfert]

Brian,

They are a good option when you are able to intergrate them into your walls or layout.

The biggest downfall, you are limited to the location of the condencers. They all vent horrizonally. which, on most occations will eat up your bay space.

We just installed a pair of 12's for Dan Odio in V.A.  and he will need a third one, with not much room left over [CFM wise]

Here's a pic of my stacked basement HP's but, I think I gave you this pic allready!

Wouldn't yours be considered package units, not mini-splits?

Mini-splits have the condenser outside, and an evaporator/blower unit that hangs on a wall inside.  I believe I have may have room for two mini-split condensers in my old condenser bay.  The mini-splits would blow out the side of the bus just as the original condensers did.

Brian Elfert

[togy48]

I have Two 1 ton units installed front and rear in a 80 Provest.In August and September ( hotest months in south Florida ) bus would be 135 F when I got home from work, fire them up and be working in 45mins comfortably. Now on timer set at 75F so I can go to work when I get home. Tonight had to shut down front unit because it has too cold inside---- outside temp 89 F

[Christyhicks]

I did something different. . . I used two high efficiency window units.  They do take up one 1/2 of a full bay, venting out through the door, but they are quiet and seem to work very well.  I tapped into the center air chase, and also added some ducts to go up behind cabinets.  I had plenums made for the evaporators and will draw my returns down through the floor under the cabinets.

I hate blower noise, and refused to even consider rooftop units.  To me, the hvac system should be quiet and peaceful, but keep you veeeeeery comfortable.

These units draw 12 amps max, under a full load, and have 99 different blower speeds. . Now, how they do that with a 120v psc motor is still a mystery to me, but it does work well.  They have programmable remotes and a coast feature, which will bring the units on for 10 minutes every hour, to stir the air a bit, for those nights when you just need a little air circulation. 

[belfert]

I did something different. . . I used two high efficiency window units.  They do take up one 1/2 of a full bay, venting out through the door, but they are quiet and seem to work very well.  I tapped into the center air chase, and also added some ducts to go up behind cabinets.  I had plenums made for the evaporators and will draw my returns down through the floor under the cabinets.

I hate blower noise, and refused to even consider rooftop units.  To me, the hvac system should be quiet and peaceful, but keep you veeeeeery comfortable.

I thought window units are usually quite noisy?   Maybe not under the bus.  What did this cost and who did the ductwork for you?

Brian Elfert

[Christyhicks]

Well, these units are actually pretty quiet, and more so when you slow the blower down.  I think that the difference is attributed to a couple of things.  .first and most importantly, anytime you duct a unit, you quiet it down, but also, I'm throwing my air through a much bigger opening than let's say a rooftop or even a standard RV basement unit.  I think my top plenums were like 12" x 4" or so, those are the plenums that come up and curve to tie into the air chase.  I also ducted, I think, two 4" supplies off each of those plenums, if I remember correctly. 

We set the window units on vibration pads. . .basically little squares of rubber and cork sold for this purpose.  Really, with the door shut outside, all you hear is airflow, and with just 3/4" plywood laid down, not even screwed tight yet (yeah, I'm chicken!), it's really quiet inside too. 

I actually had a local sheet metal shop make the plenums to my measurements, except they kind of went overboard on the thickness of the metal.   :oHe was thrilled to be even just a little part of our project, and eager to please, so he used such heavy sheet metal that I had a heck of a time cutting it by hand to make some minor modifications.  I didn't want to lose any square inches of space on the inside, so after I was sure they fit to my satisfaction, I used contact cement and glued foil insulating bubble wrap to those and the elbows and sheet metal I used for ducting. 

We will have to extend the wiring harness so that the main control boards are inside the coach, and then we can utilize the remotes if we choose. My idea is that we can use two units for immediate cooldown, and then drop down to one unit for maintaining.  When I was working on the tin can in 100 degree outdoor temps, I was able to drop it down into the upper 70's inside, and I didn't even have the entire floor insulated or the metal where we had skinned over windows.  In fact, I didn't even have all of the floor down over the bays.  . just some cardboard blocking them off.  I think once I get everything insulated, including the roof, two units will be more than adequate.  I believe they are 15,000 Btu units, and if you compare the evaporator and condenser coils with rooftop units, I can not believe that I am not getting more cooling out of these units than a person does with those stupid rooftops!  Whoops.  . :-[I mean, than with rooftops.

Now, ask me how many times I stepped down through the "cardboard floor" while I was inside working!  Thank goodness for the sewer tanks that we slid into the bay until we get them mounted!      Luckily, both times, those tanks stopped my rapid rate of descent until I was able to get my balance again!  Course, it sure did poke holes in my fine cardboard floor!  Christy Hicks

[DROdio]

I have two 12,000 BTU soleus air units on my bus.  I might need to add a third; don't know yet because i haven't been able to use the bus yet!.  pics at www.WonderlandBus.com

[Rodsmc5c]

I did something different. . . I used two high efficiency window units.  They do take up one 1/2 of a full bay, venting out through the door, but they are quiet and seem to work very well.  I tapped into the center air chase, and also added some ducts to go up behind cabinets.  I had plenums made for the evaporators and will draw my returns down through the floor under the cabinets.

I hate blower noise, and refused to even consider rooftop units.  To me, the hvac system should be quiet and peaceful, but keep you veeeeeery comfortable.

These units draw 12 amps max, under a full load, and have 99 different blower speeds. . Now, how they do that with a 120v psc motor is still a mystery to me, but it does work well.  They have programmable remotes and a coast feature, which will bring the units on for 10 minutes every hour, to stir the air a bit, for those nights when you just need a little air circulation. 

[Rodsmc5c]

 
        How did  the window units work out??  I am just about at that point in my conversion and it sounds like a novel idea. I can always put in roof-tops if I need to, the wire is already there. Do you have any pictures of the installation?
                                Rod

[tekebird]

split units have been used in marine and professional conversion since the 70's......and still used today.

That in itself should answer the initial question

[Busted Knuckle]

The mini-splits would blow out the side of the bus just as the original condensers did.
Brian Elfert

Brian not that it really makes much difference but I think if you check it out the original condensers pulled in the side and out the bottom! Like I said I don't believ it makes a hill of beans worth of difference for what yer do'n, but that is the way most of the OEM units do it!

And as a side note to the OEM units exhausting out the bottom which can creat some thick dust clouds any where there is dust/dirt on the ground. We take an old mudflap or a peice of old conveyor belt and make a horizonal flap suspended by chains under the exhaust to deflect the air out instead of straight down to keep it from clogging the condensers, and also keeps coach cleaner.
BK 

[belfert]

Somebody dragged up a thread from early May.  I long ago decided to go with two 15k roof top units.

The mini splits would just take too much space for the condensers and be hard to cool.

Brian Elfert

[TomC]

Would highly recommend you use a split system made for a vehicle.  Like the CruiseAir, or especially the Tundra either all in one or split system where the condensor is outside and the evaporator/compressor is inside.  Go to WWW.Tundra.CC for a look-under truck systems.  Good Luck, TomC