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
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.
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
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.
Quote from: jraynor on June 28, 2018, 05:44:05 PM
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.
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?
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.
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.
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.
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
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.
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
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.
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
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.
[.
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
[/quote]
So does the 2.4 million Marathon Prevost run 4 roof tops 60,000 worth of BTU for cooling plus the over the road AC while driving
I painted my roof air covers to match the primary color of the coach and they just blend in. Plus it makes the bus look like an RV so the highway patrol doesnt think you are a commercial bus to pick on.
I just don't like the noise of roof units when I'm suppose to be relaxing==and a lot of the Tractor shows we go to your lucky to get 30 amp @ 120 volt. Roof top units are the way for new converts=less time to just plug and play. Big thing is do it your way!!!! No way is wrong in this hobby...
I just did a quick online search to see what other non-traditional options are out there. Here's one that might be an option to replace an OTR unit, since it runs off of DC and draws less than my OTR condenser fan alone.
http://www.guchen.com/electrical-truck-air-conditioner/ep-02g.html
Another consideration may be the extra top weight over time. If you end up with three, (3) or even perhaps four, (4) roof top warts on your Bus Conversion the pounding over time and mileage may have detrimental affects on your roof structure.
The other considerations may be the additional roof height. Low bridges. Branches. Gas station overheads. Etc. The additional highly mounted weight may or may not affect road handling. Using escape hatches for roof A/C may not work either.
WoW. Roof airs are so noisy and you will tip over from the weight and they are for newbies. And you will hit underpasses.
I don't think so.
LOL
Geoff
The only reason I used the Crusiair on my Eagle is I wanted a clean roof line
What turned me to the Roof Airs was when talking with Gumpy last spring, that along with wanting keep a good bay or bay and a half free for storage and other stuff is nice. Then add the easy replacement, etc it became more palatable. It might not be best or most efficient, but they do seem quite practical.
Quote from: richard5933 on June 29, 2018, 03:48:19 PM
I just did a quick online search to see what other non-traditional options are out there. Here's one that might be an option to replace an OTR unit, since it runs off of DC and draws less than my OTR condenser fan alone.
http://www.guchen.com/electrical-truck-air-conditioner/ep-02g.html
Interesting, but they do not seem to have a distributor in the US. :-\
Wow??😮
I did a little test today on the roof top on the Trek a HVAC guy told me to do, you guys know a roof top will blow almost 15 degrees colder on low than it will on high that surprised me .
Temps here in Wisconsin today are pushing 90. Actual temp is 87 with 74% humidity. When we woke up this morning the temp was 75 and humidity was about the same. Feels like walking through a sauna today.
Today is the day we're installing a new fridge in the bus, so I got up at 4:30 and turned on the a/c in the bus. It was off for the past few days. Both basement a/c units are running. Within about an hour the temp in the bus was 74 and the humidity down. With the sun beating on the bus all day the temp is still 74 and the humidity is still down. The units are cycling on & off pretty nicely, with more time off than on once the temp and humidity were stable.
The only modification we've done to help them work was to cover the inside of the windows with Reflectix so the sun doesn't bake the interior.
I know that this is not Arizona weather, but it is a pretty good example of two older basement units able to pull their own weight. At least for now.
Ya but Richard thats like Wet heat! Its so like todays post, I mean you got the Misters On.
I just couldnt help myself on that way down here in Missouri today, its a bit hot.
You should have some chilled cold ones nearby, while monitoring the new fridge :)
Good day
Floyd
Quote from: luvrbus on June 29, 2018, 08:13:59 PM
I did a little test today on the roof top on the Trek a HVAC guy told me to do, you guys know a roof top will blow almost 15 degrees colder on low than it will on high that surprised me .
That normal for all AC's. Just consider it. When the unit is on, it is extracting its capacity of BTU's . If you push more air through the coils, you get more cold air but at a higher temperature. Or slow down the air flow and get less CFM but at a cooler temp. Either way, the heat transfer is roughly the same. It will also dehumidify more at lower speed.
I like mini splits. They are quiet and efficient. However, our bus has roof tops. They are huge ancient ones. I can see how many feel that they are unsightly but one could argue that that is one of their charms. It is sort of a rough beauty-- like a cactus. My biggest complaint is that the high air flow makes them noisy. At night, we generally just turn the front unit on and leave the bedroom door open. It cools enough and is less sleep disturbing.
When air traveling this past year I bought some noise canceling headphones. Maybe I'll try them on our next summer bus trip. The big advantages have been repeated here several times: easy, dependable, low maintenance, no loss of space, etc.
last time out when I was using the roof top a/c I could smell outside air
( diesel from the aqua hot ? ) coming in ? so when I got home I removed the top cover and unscrew the metal cover on the unit . I could see that the thick foam insulation ( 1/4 " ) crap . that it had been leaking in air from out side for a long time . so I used some tinfoil bubble insulation that I had to re insulate the cover from the under side and used a good quality tin foil tape to hold it on the edges . had to do that on the 2 front units . the rear was a newer unit and was still in good shape . it sure made a difference on the a/c and now no outside smells in side when the a/c ,s are on and they are pulling the return air from the inside of the coach and not from the hot outside air .
I like the split unit on the M C I better then the roof top noise makers on the featherlite . but after you get use to the noise they work good
the 2 front a/c units are 18 years old and have the heat strips and the rear unit is maybe 5 years old ? with a heat pump and for the heat part I like the old heat strips better then the heat pump other then the burnt hair smell when you first turn them on
dave
This is my third year with mini splits. I don't venture into the southwest for the super hot but, I have used them in near 100 degrees, sitting in the sun, and been quite comfortable. I still haven't gotten extra insulation in the roof yet. They are quiet, even the rear one that has the condenser under my bed, I only get a sense that it is running I don't hear it. I have two 12,500 btu units and total amp draw is less than 20 running in the heat. I have the inverter type and amp draw on start up is 2 slowly climbing to about 7 on each unit. I probably use them as much for heat on those chilly spring and fall mornings as for the cool.
Only time will tell if I have problems with vibration. If I do it will probably be in the condenser unit. As for the copper lines between evaporator and condenser, buses have been running copper water and air lines for a long time.
I also think roof airs are ugly but, that's just me. I think they also have to effect fuel mileage but, again that's probably a moot point on a bus.
Thumbs Up!
Always good to hear about some of these installations. By the way whats the location area of the other condenser. Can ya give some thoughts on that space and any tips or ifs with both these condenser spaces. Thanks
Good day
Floyd
Had a friend stop by Monday that just removed his 2 Sanyo inverter type mini's and replaced with 2 Dometic self contained units I have photos I am going to post on the MCI group on F/B nice looking units but I didn't ask the price
Quote from: brmax on July 03, 2018, 06:16:13 AM
Thumbs Up!
Always good to hear about some of these installations. By the way whats the location area of the other condenser. Can ya give some thoughts on that space and any tips or ifs with both these condenser spaces.
I have a RE skoolie, the front condenser is lengthwise is between the frame rails right behind the front bumper. Since about half of it is between the frame rails I had originally thought that I might have to somehow separate the intake air from the exhaust with some sort of ducting but, it doesn't seem to be necessary.
The rear one is in the location of the original factory condenser. Since it is basically in the engine compartment I mounted it so it would take air from the engine compartment and blow out. The reasoning is that it isn't likely that I would ever use that unit while traveling and with that side to the sun it would be much hotter after the engine cools down.
Quote from: luvrbus on July 03, 2018, 07:31:09 AM
Had a friend stop by Monday that just removed his 2 Sanyo inverter type mini's and replaced with 2 Dometic self contained units
What was his reason for doing it?
He told me he was just tired of the P17 Code ? and needing a box fan blowing on the outside unit,he is the 3rd one I know of that removed the Mini the others like their Mini's and deal with what ever problems they have
Just curious, may have missed the discussion. Is it possible to relocate rooftop AC into the bays, mod as necessary for routing the air into the coach?
I'm no fan of those warts on the top either and being more quite would be a nice benefit although the ones in place now are pretty quiet.
I think that Tom C has done something like that. If he doesn't join in, you could PM him.
I have mini splits on my coach, two heads on one unit. Buy a brand that is supported and you can get parts. There is a lot of units from china that have no support.
Thanks Art...What brand did you go with?
Dankin because parts are available.
Hart,how mutch BTU you are running from your unit ?
In Sicily it gets into the hi 90s, mini splits are King in ancient buildings that added AC, lvmci...
Quote from: lvmci on July 17, 2018, 01:15:42 PM
In Sicily it gets into the hi 90s, mini splits are King in ancient buildings that added AC, lvmci...
Lol Tom those buildings haven't moved in a 1000 years
Except for that leaning tower up north.
Just had an H3-45 pass us on the Pa. Turnpike today. It had about 4 or 5 roof airs. Man, he better stick to interstates.
Since my truck conversion is 13'6" tall, no room for roof top A/C's. Dometic Penguin is capable of converting to basement air's with some modification and ducting. I ran one, it is is really quiet-can't even hear it in the bedroom.
Don't worry about noise with rooftop airs. As you get older, your hearing goes away and it'll get quieter.
Quote from: TomC on July 18, 2018, 07:53:21 AM
Since my truck conversion is 13'6" tall, no room for roof top A/C's. Dometic Penguin is capable of converting to basement air's with some modification and ducting. I ran one, it is is really quiet-can't even hear it in the bedroom.
Tom, I am considering using some of the Penguins I have in the spare tire area up front on my Eagle. I would really like to hear more details about where and how you did yours. I get that the cold air has to be custom-ducted out, but what about cooling air flow for the unit, and devising remote controls? I have a 250V basement air main unit, but I would like supplemental A/C and backup that would run on 125V for campgrounds that only have 30 Amp. Your picture shows the unit on its side, is that just for the picture, or is that how you are mounting it?
A regular house window AC unit can be ducted in a bay, and has the advantage of working off the side of it, instead of the bottom of a roof top.
Remember, you have to deal with the condensation from whatever home brew you choose!
happy coaching!
buswarrior
Been wondering for awhile why there isn't more discussion around using window AC or two in the bay with ducting into the interior. Seems like a very practical and inexpensive way to do it. BW post is first I have seen in awhile.
Quote from: windtrader on July 18, 2018, 05:01:26 PMBeen wondering for awhile why there isn't more discussion around using window AC or two ...
Round these parts, that's called the "redneck's air conditioning system". It's illegal to drive a "pop in" pickup camper without one in several states.
Quote from: windtrader on July 18, 2018, 05:01:26 PM
Been wondering for awhile why there isn't more discussion around using window AC or two in the bay with ducting into the interior. Seems like a very practical and inexpensive way to do it. BW post is first I have seen in awhile.
because cool air doesn't rise ?
I'd assume an inline fan can move colder air from the bay up into the coach interior. I'm not a redneck so I must be missing something. :-\
We don't bother with a/c, yet. But I did have an idea at one point to install a house window unit by cutting a hole in the side of the bus under a window. Then I was thinking you could either use a fridge side vent or make a nicer door like many RVs use for their storage bays. It would be pulled into the bus when you moved. For those of us who don't move all the time it would be an option. The major advantage is cheaper and window units pump quite a bit of cold air.
But, there's many reasons we never did this. I don't think we will. It's ugly. :) maybe if we park the bus on our own land permanently someday...
If it gets too hot to be somewhere we move on. Someday that'll change and we'll probably go with the split units.
I have a friend that built his own AC using the drivers AC evaporator in his bus (MCI) ,he added a Copeland compressor and condenser from something works good using 134A Freon.Electric fans replaced the DC motors has a BTU rating of 45,000 nice and quite with no extra holes cut in his bus.Probably not something the average bus person could do but he is a HVAC contractor so it came easy for him.People have been splitting the window units for years to use in a bus one comes here to the shop the owner did 25 years ago
I've kept my in dash evaporator in case I decide to go that way down the road.
The unit is tilted just for the picture-it runs in the normal position on a pedestal high enough to facilitate the return and cold air (about 23" tall overall). Had special 8" duct made for return and 6" duct made for hot air from condenser. My units are of the molded plastic and metal fans. I understand that they are now styrofoam and plastic fans. Order 15,000btu units-same compressor, but more powerful fans for ducted and remote thermostat. Good Luck, TomC
Quote from: chessie4905 on July 19, 2018, 07:31:53 AM
I've kept my in dash evaporator in case I decide to go that way down the road.
It is a good idea I am restoring my dash air and it is costing a arm and a leg for parts to run from the engine
Quote from: windtrader on July 18, 2018, 10:20:57 PM
I'd assume an inline fan can move colder air from the bay up into the coach interior. I'm not a redneck so I must be missing something. :-\
i only meant that a bus needs to be as efficient as possible.
regardless the amount of insulation.
where does redneck play into this discussion ?
Quote from: eagle19952 on July 19, 2018, 08:10:03 AM
i only meant that a bus needs to be as efficient as possible.
regardless the amount of insulation.
where does redneck play into this discussion ?
Yep a bad choice of words most bus owner do have a little red neck when it come to modifying any part of a bus 8)
I like the idea of re-purposing the existing condenser and evaporators. Now here is another thought to consider:
Heat pumps use a shuttle valve for the purpose of allowing full flow in one direction and an orifice for reverse flow. Actually I think they must have two of those, one in each line on either side of the "A" coil but not being a full fledged A/C tech that's just a guess. There's more to it obviously. Anyway, why not just run two compressors in parallel? One on the engine and another electric unit run from the shore line? Might need a check valve or two in there somewhere to keep from bleeding pressure back through the pump that wasn't being used (or not) but it seems like this could work.
Mismatched component sizes... yes that would have to be dealt with. The shoreline compressor is not going to be anywhere near the size of the engine driven pump. Just filling the liquid line would take a bit of time and the expansion valve would have to be able to close down to a veritable trickle somehow. Not sure how to do that but there must be a way.
Sounds kinda complicated but if enough redneck minds attacked the problems I'm sure it could be done.
If it was figured out you still have a big system with lots of refrigerant but maybe you could spec a cheaper, more available refrigerant.
Jim
Quote from: GnarlyBus on July 19, 2018, 12:44:11 AM
We don't bother with a/c, yet. But I did have an idea at one point to install a house window unit by cutting a hole in the side of the bus under a window. Then I was thinking you could either use a fridge side vent or make a nicer door like many RVs use for their storage bays. It would be pulled into the bus when you moved. For those of us who don't move all the time it would be an option. The major advantage is cheaper and window units pump quite a bit of cold air.
But, there's many reasons we never did this. I don't think we will. It's ugly. :) maybe if we park the bus on our own land permanently someday...
If it gets too hot to be somewhere we move on. Someday that'll change and we'll probably go with the split units.
That's basically what I'll do for my bedroom. A small 5K window A/C will fit into the rear roof cap above the bed, and the front of it will be have a door just like the overhead storage cabinets on either side of it, so there's nothing to see when it's not working. And it should run for several hours off my house batteries if it's a stinkin' hot night, assuming I haven't driven to somewhere cooler instead (isn't that why buses have wheels?). Yeah, they're noisy, but that's what earplugs are for.
And for the rest of the bus, a 12K inverter mini-split with heat pump running off solar - yes, it can be done!
John
Quote from: luvrbus on July 19, 2018, 08:47:27 AM
Yep a bad choice of words most bus owner do have a little red neck when it come to modifying any part of a bus 8)
LOL..We called it something else..I think the politically correct name now is African. :)
Has anyone used an office type a/c unit before. I have someone local who is sell some and he is asking $1500 each ($1300 each if I buy 2) and they are 1.5 Ton (17,300 BTU to be exact). These can easily be ducted as they blow from a vent on the top (I think they actually sell a type of adapter)
What does everyone think?:
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&cad=rja&uact=8&ved=2ahUKEwjB6Y-mrszcAhUl0YMKHTAnD0kQFjABegQIAxAC&url=https%3A%2F%2Fwww.portableac.com%2Fwp-content%2Fuploads%2FSpec-Sheet-1.5-Ton-Spot-Cooler-TZ-18A-18B-HA1.pdf&usg=AOvVaw3WMKiRHVSLr7KHY2h5lw1-
According to Amazon, they are $4K each new. I imagine that the control wires could be extended into the bus pretty easily.
Would these be better over the $900 Costco MrCool Split units?
Thank you
they work well. I have seen them in a number of stores and cafes that don't have central air but for a bus can you give up the floor space?
Quote from: jraynor on August 01, 2018, 10:54:38 AM
Has anyone used an office type a/c unit before. I have someone local who is sell some and he is asking $1500 each ($1300 each if I buy 2) and they are 1.5 Ton (17,300 BTU to be exact).
Would these be better over the $900 Costco MrCool Split units?
Thank you
I bought one of these for my mother to use while the central air is being replaced. At $500.00 i would consider two of these before $2600.00 worth of those.
it makes the kitchen/den area (800sq/ft and open to the rest of the house..there are no doors to close the area off) easily tolerable in Alabama 98 degree days with 110 degree index and unbearable humidity. She is 98.
Yes, i was skeptical.
I would buy another.
https://www.lowes.com/pd/Hisense-500-sq-ft-115-Volt-Portable-Air-Conditioner/1000338609 (https://www.lowes.com/pd/Hisense-500-sq-ft-115-Volt-Portable-Air-Conditioner/1000338609)
PS there is/was a smaller unit in the bedroom :)
PSS...condensate tank is not a factor with the Hisence.
Quote from: Lee Bradley on August 01, 2018, 12:00:20 PM
they work well. I have seen them in a number of stores and cafes that don't have central air but for a bus can you give up the floor space?
Ideally, since they are ducted, they would go in the basement and come up through a wall or even duct into the original ducting for the front. For the back, I would place it in the engine bay with its own box (to keep it from drawing air from the engine bay) and duct it up behind the back wall.
eagle19952,
I actually have one of these for my house that I use rarely. I want to have a central system type setup for the bus. The only downside to the unit I posted and the one you posted is that they don't have a heat pump like the split systems do. Right now im still leaning towards 2 12k BTU split systems
Mini splits are struggling here today @118 and asphalt temp @ 145 I had to move my bus out of the shop so a friend could move in, he couldn't find enough of a shady spot in the RV park to make his work and it is friggn hot with humidity
Makes a person like me in the midwest wonder?
What are the central air units in the southwest peforming like.
They must be as here typically mounted on a concrete pad.
The topic sure keeps me considering options.
Good day
Floyd
My outside unit does ok setting on the pad in the shade and drawing air from 3 sides ,his mini splits just have 1 intake, we have cold front today a high of only 109
Quote from: luvrbus on August 02, 2018, 07:07:38 AM... we have cold front today a high of only 109
It's OK, it's a dry heat.