built in air conditioner.
 

I have been searching for a built in ac system for my build, does anybody know of such a beast?

as in a mini split or basement model?? Both very spendy, tell us what your plans are...
-blizz

I have a md International truck that I am building 20 ft of living space and a drop down garage in the rear for our racing karts. I only have 12 ft. doors in my shop so I am trying to keep the height down. I am putting a lift in the garage to store spare karts so I need to keep the inside height as tall as possible.

I have been using a mini-split style system for the very same reason ie:height. I had mine installed by a home HVAC friend of mine. It works great. The only advice I would add would be to secure all lines tightly. We had a few leaks in the begining, because these AC units are not designed to bounce down the road. Since we re-secured everything it has been fine.

Those home style mini-split systems seem pretty nice. I was talking to a guy at the hdt rally last October about his. He had one installed in the sleeper of his tractor. They had lots of problems with it and ended up removing it. He said they decided it just wasn't up to the abuse of going down the road. I don't know what brand he was dealing with. I do know it was a shop that was doing all his work so it wasn't like they didn't know what they were doing I don't think. Maybe putting one into a living quarters box wouldn't be as rough as the sleeper on the truck? I think somebody makes ac units that mount down below and duct up to the roof though. My neighbor's 2 year old Winnebago doesn't have roof air. His a/c is down below. I never really looked at it so I don't know what they use. And his is in storage now so I can't go over and check it out.

I think coleman used to make a self contained heat pump unit for the basement of motorhomes, but i believe they stopped making it, not sure if anyone has made a replacement for it yet. biggest problem with the mitsubishi mini split units in a road vehicle is making sure the copper line sets are properly mounted, constant flexing of the copper line causes it to harden and then crack. also make sure the condensing unit is mounted somewhere out of the path of the moving air while driving down the road or the fan will be spun by the air and ruin the bearings. (the company I work for builds mobile office trailers and we learned this the hard way.) The great thing with the mini splits is you can put up to 3 indoor units on one outside condenser. That way you can have three different temp zones for different rooms. electrical draw is also about the lowest of any heat pump.

Regardless of mounting style, you are on the right track with a heat pump vs. normal a/c unit. I used a 15,000 btu Carrier roof heat pump in our trailer instead of the normal 13,500btu a/c that you usually see. It was not that much more than an a/c unit, and you get full heat output out of it instead of just cooling. The heat strips in a std. a/c unit are entirely useless, but this works quite well. We've had this on working well with days into the 90's, and sometimes nights into the 40's and it keeps up just fine. A basement heat pump makes sense for the same reasons. One unit for heat and cool.

Another thought just came to mind. What about one of those Bard a/c units? I think that's what they're called. I see enclosed race trailers advertised all the time with those. I think they mount those to the front of the trailers. I wonder if you could lay one down on top, or underneath? They must be heavy duty.

Thanks for all the responses it gives me alot to think about, I just can't beleive there are not more companys building them so people can get rid of the roof mounted units.

We use the Bard units on our potable office trailers and classrooms all the time, However they are fairly heavy, draw quite a bit more power, and make more noise and vibration than the mini splits. Biggest advantage for us is they are self contained, no refer piping to deal with and cheaper. All but the smallest (12,000) btu are set up for a supply duct up high (usually in the attic or above a suspended ceiling, and a return grill through the wall. They work great on the larger race trailers with either shore power or big gen-sets. One other drawback is if you four season camp, the heat pump portion does not work well in cold climates, needs to have the auxiliary heat strip option that will add an additional 40 amps to the power requirement.

Harry
 

Hi I know that winabago moter homes use a basement AC its self contained and all you add is duckwork to were ever you want
Hope this helps
Harry

Harley, I just happen to have a new (never installed) Coleman basement air/heat pump, complete with integrated thermostat & wiring harness. I think it's a 30,000 btu unit but I would need to look at the spec plate to verify. I had purchased 3 years ago with intentions of installing in an MCI-9 bus conversion. I ended up selling the bus without the ac unit. I would sell reasonable, as I ended up with roof air's on my truck & don't need it. contact me if you're inerested. bobsquad7@cox.net

that sounds great I sent you an email

Someone mentioned that minisplit systems are expensive. I found a unit here that is pretty reasonable.
MiniSplitShop.com :: One-Zone Mini Split :: Soleus (Heat Pump) :: 9,000 BTU Soleus Mini Split A/C + Heat Pump - 115 V

I doubt that I can get a rooftop unit for $400. My rooftop is getting weak and I want to use one of these. I just have to work out where I will put the compressor unit.

Andy, for what it’s worth here is my thoughts. This is an excellent price for a split system heat pump. That said here is how it compares to the more expensive systems such as Mitsubishi, This unit has a single speed compressor, the unit is basically on or off and cooling/heating is varied by changing the fan speed. The higher price units use inverters to run a variable a speed compressor that will adjust its speed (affecting noise and power consumption) based on temperature. The lower cost units will produce significantly less heat when outdoor temp is below 40 degrees. (This may not be an issue if you have a gas furnace in addition or do not use in cold climates.). With the lower cost units you can only have one indoor unit per compressor, if you only have one room or area to heat, again not a problem, though it is nice to be able to use only one outdoor unit, to control two indoor units for living and sleeping areas. As far as installation goes, make sure you download or find out the clearances needed for the unit before you buy. Some of the outdoor units require quite a bit of clear space to function properly. If there is not enough space or airflow, compressors can overheat or the coils can ice over due to lack of air flow. Try to make sure the outdoor fan is not directly in the path of wind while driving down the road, this will cause the fan to spin faster than it’s designed to and can ruin the bearings. Remember all the mini splits are designed to be used in a stationary building not running down the road, so some additional thought must be used for securing and installation of equipment and piping. If the unit does not come with a copper line set, you will need to order that also. The units are easy enough to install and wire, however I recommend that you use a HVAC technician to connect and test the line sets, he will check for refrigerant leaks and ensure you will have trouble free service. (the unit should come pre-charged with the proper amount of refrigerant.) I think we have paid around $200-$300 to have someone connect and test the systems in the past that we have used. I cannot speak to the quality of this particular brand as I have not used them before, I have experience with Mitsubishi and Fujitsu, and I think that the mini split in general is a great system, and with their low power consumption (800 watts/ 7amps on this unit) they are perfect for RV’s, I plan on using one of the multi systems in conjunction with a diesel boiler on my next rig.

Dave

Thanks Dave. You are correct about the inverter units and I would probably spend more to get one. I use my rig to travel to antique steam and farm equipment shows where power availability is a problem. The low amperage needs of the inverter type could mean the difference between having AC and not having it. You also make good points about the installation. Dad is converting a 45' Prevost right now and he is using minisplits in it and we have been paying special attention to these things. Dad was also a refrigeration guy in a previous life so his experience is very helpful. My little 12' box should only need one indoor zone and I think 9000BTU should do it.

Mine is a Friedrich mini split and has bounced all over the nation. I am using one for the front half of my box (back half storage) and it works great.
True Dat:
have tech install it.
secure lines WELL
give it air (keep it away from your generator)