Roof air or mini split??

[OKIE9ERS]

Been reading good things about mini splits in general...Seen several posts from years ago...Anyone have recent experience with them?
I saw where one issue with them was the lightweight copper tubing was not too good for bouncing down the highway, lines and fittings cracked.
Wondering why you couldnt use rubber lines like cars and trucks use to deliver the regrigerant?
A/C is just one of my decisions to make...still in the very early stages of converting this old beast...
Thanks

[richard5933]

We have two units which are a 44-year-old version of a mini split system. Compressor and condensing coil in the bay, evaporator and air circulation blower in an upper cabinet. Lines between the two are copper tubing. Seem to be working fine after 44 years. Others are using modern mini-splits with success, and I'm sure that they'll chime in with their experience.

[jraynor]

That is what I'm planning to use. Considering locating the outdoor unit in the engine bay where the toilet tank used to be and mounting the indoor unit in a box where the freshwater tank for the toilet used to sit. From the box I'll duct it towards the front of the bus. I was originally going to go with only 1 12btu unit but I'm not sure how well that will cool when parked. I just want to stay away from the roof top units. No holes = no leaks

[Geoff]

I have 3ea 15k Coleman Mack's and they kick a$$.  I just got through working on a 4104 with two Cruise Air's, and I thought they were weak.  But they were installed in 1998.  Maybe new units are better. Oh, my roof tops have never leaked in 12+ years.  It's all in the installation.

[richard5933]

That is what I'm planning to use. Considering locating the outdoor unit in the engine bay where the toilet tank used to be and mounting the indoor unit in a box where the freshwater tank for the toilet used to sit. From the box I'll duct it towards the front of the bus. I was originally going to go with only 1 12btu unit but I'm not sure how well that will cool when parked. I just want to stay away from the roof top units. No holes = no leaks

Sounds like it might work, but two thoughts...

1. The engine bay can be very hot and may affect the ability of the outdoor unit to shed heat.

2. There are some low-pressure zones towards the rear of the bus, so you may/may not have to install make some modifications or do some sheet metal work to force the air to the condensing coils.

[jraynor]

Yeah that has been a thought. I'm hoping to get units that have a fan to pull/push air across the coils, but if not, I would install a fan. But ideally, I'm hoping to have the over the road A/C for traveling and only use the split system when parked so no heat from the engine compartment. How do y'all provide air flow with the condensors in the basement?

[chessie4905]

Although some consider them unsightly, roof airs are the best for good, quick initial and satisfying cooling. The biggest complaintsI've seen over thousands of posts are that they are unsightly, noisey, and leave condensate stains on roof sides. As far as leaking inside, almost all with that problem is the result of installation issues.
My dad's 4104 had two 12,000 btu, probably Cruise airs installed in bay with ducting when converted.
At a particular weekend rally at Tilgmans Island in Maryland, He commented to my brother how it took a while to cool off on the hot day. Brother said his was already nice and cool and had two 12,000 btu roof airs. Father didn't believe him till he went over to verify. The next week, two roof airs were ordered and the basement airs were removed along with their ducting.

[robertglines1]

today at noon 105 feels like--97 F actually. My bus is outside on pad because I have truck over pit.  one 9,000 inverter style running. 74F inside. I have 2each 9's and 1 each 12 thousand.They pull 6 amps @  120 volt for 9 and 8 amps 120 V for the 12. Nos start up spike(load ) on the inverter style.   Suggest you hook up drains on both ends of ponding  box. Spend the big bucks on insulation. No rubber hoses=your dealing with higher pressures with r 410a plus heat being carried away back to evap.  window shades--and fewer windows are you friend here. User since 2012.  Hope this sums things up.

[chessie4905]

Only used when parked, so no heat from engine.... That engine is going to be hot for at least 4 hours. Keep that fact in your calculations.

[luvrbus]

I think it will be a long time before the converters start using mini splits if they ever do .People love or hate the mini splits I have friends on both sides of the debate one tossed his the other added another 9000 btu unit

[chessie4905]

You have a mini split for 4years and it works well, then the compressor goes bad. Company no longer in business or replacement unit configured different. Won't work with evaporator unit. New ones different size, so location needs reconfigured to make it fit...
Have a roof air. Compressor goes bad. As with mini split, replacement compressor costly. Replace unit. Goes in same opening as old one, and connects same. In and done. Just something to think about. Sometimes people get all excited about new technology just for the sake of it being the latest greatest energy saving thing. If you are building the conversion for enjoyment travelling and camping, relialibility should be foremost. Just my thoughts and experience from being a conversion user for many years.

[luvrbus]

My thought on the mini if you are paying the electric bill or have a tiny generator I would give it A+,the unit on the inside wall would be a C,the storage lost in a bay would be a D, dependability some folks have problems others don't so like all things it is a personal preference.
I do think they could improve on the roof tops though, Dometic took a good Penguin Ac unit that would last and cool and screwed it up with the new Penguin ll that is just junk       

[chessie4905]

I think that there could be major improvements to roof air units also.Just like Norcold refers. We just need more competitors, but I guess not enough are sold to make it worth the investment. Maybe now that rv's are getting popular again, someone will come up with quieter, more efficient, more compact units. I'm not holding my breath though.

[TomC]

Much like Geoff, I have 3-13,500btu Coleman roof tops with heat strips. If you close off the vents, the heat strips do work well. I have the front A/C mounted so it blows on me while driving, and with an additional dash fan, I'm fine driving even in 108 degree weather. 2 usually cool just fine. I installed them in 1993-besides just cleaning the filters and having to replace one outside shroud, I've done nothing to them and they still work great.
Main argument for roof airs is easy replacement if they take a dump. Yes they are unsightly-but you'll notice even the Newells ($2 million) have 4 roof airs. Good Luck, TomC

[chessie4905]

Also, all the crud that develops in air flow to inside of coach from much use is minimal. The ducted jobs just keep building up the crud in the ducts over time and I don't know how difficult they are to clean. Hopefully not as bad as the factory otr air ducting.