Anyone actually install mini split heat pump on camper?

[bstory]

Hi all,

I have been interested in using one of the newer combination AC and heat mini splits on our Sprinter camper. We have them at the house and love them and they are much, much quieter and more efficient than other options, plus if you want/need both AC and heat, not a bad buy.

However, before we actually do this, I am worried about the outdoor unit getting bounced around on rough roads and whether the manufacturer would honor the warranty if installed for mobile use.

Anyone know of an actual install and if so, how the units have held up after some months on the road?

Anyone know of a manufacturer that has been accepting of this sort of use?

The 12 volt ones for big truck rigs are too big and too expensive for us. Plus most only are AC.

The 115 volt ones for big RVs are too loud and too power hungry.

We are getting by with fans and good ventilation in the heat and a portable heater for the cold, but would like to continue to explore this idea.

Any evidence or experience would be much appreciated.

 

[doug720]

Our Winnebago class A MH has a basement unit AC/Heat pump unit.

The AC works great, but the heat pump is marginal, and the coach has a conventional propane forced air heat system. Ours is a large unit and requires a large amount of generator power or shore power to run, so not really practical for dry camping, which we normally do. The propane runs of 12v.

If you have a diesel, check out the diesel heaters, no/low power to run and very frugel on fuel with great heat. We had one on our boat.

Doug

 

[bee]

I am really interested in this as well.

 

[mhiscox]

I've been trying to figure this out for years and I'm not sure it can be done without the potential for a total fail. As pointed out, the units aren't necessarily made to be bounced around, and the precharged linesets that these units require aren't likely to be what's needed for any given design. I agree about the noise and power requirements of the rooftop units, but given that even million dollar coaches still use them, you have to figure if something clearly better was available, it'd be in widespread use.

That said, the very upscale Kimberley Kruiser off-road caravan can incorporate a split system. Check here to read about it:

http://www.kimberleykruiser.com/super-quiet-12v-air-conditioning-system

and decide if you can make anything similar work for your unit.

After more or less giving up on the split systems, I have spent some time working out how to use a floorstanding 120V portable unit like this:

These are quieter and more energy efficient than rooftop units and will work OK if you have a good scheme to exhaust the air. Window units can also be used sometimes, as I did in my original Sprinter. (Both of these types have an advantage in Oregon by being removable when not needed, which is the majority of the time in Oregon's relatively temperate climate.)

 

[bee]

One of the big advantages of mini split systems is that they generally are "soft start" and infinitely variable speed compressor, which makes them ideal for solar power.

The soft start doesn't surge allowing it to be powered from smaller inverters or smaller generators.
A single 2000w "suitcase generator" could easily power a mini split. The smallest generator capable of powering a standard A/C unit would be a yamaha EF2400. Thats 75lbs vs 44lbs between the 2 generators, plus size, fuel consumption, etc.

My guess would be that mounting the units with rubber isolators, and preventing the outside fan from being turned to fast by the wind when driving is all it would take. I would consider using rubber hose instead of copper tubing, to aid in installation.

One benefit over smaller systems like those used in 18 wheelers (pretty sure similar to that kimberly unit)is that when you are being powered from shore or generator you can crank the A/C to max and have some decent cooling, when on solar you can still run it on low and maintain cabin temp.

 

[LeishaShannon]

We're using the Mitsubishi SRK20ZJX-S 2.0KW on our camper, it draws just 350W on high and because its a variable compressor can run as low as 190W. In a well insulated camper it will have quite short cycle times so its possible to run off solar with an appropriate inverter / battery bank. We have 1500W of solar, 360Ah @ 24v of Lithium batteries and 2 x 1600VA Victron Multiplus in parallel and have no problem running it.
The main issue is the compressor movement on the road which will eventually work harden the copper pipe. A bolt or two through the bottom plate to prevent movement of the compressor should help prevent this, just remember to remove it before use

 

[ianc]

When you say a split heat pump do you mean something like this: https://www.dometic.com/enie/Intern...ners-Ventilators/product/?productdataid=66886

We've fitted one of these. The heating can be best described as gentle. I've yet to test the AC in anger was we've not travelled outside Ireland yet!

 

[bstory]

Well actually, more like this:http://www.ajmadison.com/cgi-bin/ajmadison/FRS09PYS1.html

These are widely used in buildings in the US but not yet in mobile applications. The combination of a wall or ceiling mounted air handler inside and the compressor/heat pump unit outside means you have something much quieter and the technology used means it is much more energy efficient than regular AC. You can also have heat. I have the Mitsubishi Mr. Slim units in the house. One is just AC since we have other heat downstairs, but the upstairs one is both heat and AC and the heat is good to heat two bedrooms in zero degrees fahrenheit without a problem.

A few people have rigged units up but I was wondering about 1) problems after a year or two of road vibration on them, and 2) warranties for mobile use.

 

[tanddvrchota]

We're using the Mitsubishi SRK20ZJX-S 2.0KW on our camper, it draws just 350W on high and because its a variable compressor can run as low as 190W. In a well insulated camper it will have quite short cycle times so its possible to run off solar with an appropriate inverter / battery bank. We have 1500W of solar, 360Ah @ 24v of Lithium batteries and 2 x 1600VA Victron Multiplus in parallel and have no problem running it.
The main issue is the compressor movement on the road which will eventually work harden the copper pipe. A bolt or two through the bottom plate to prevent movement of the compressor should help prevent this, just remember to remove it before use

LeishaShannon: do you happen to have pictures of your setup. The inverter system is something I am interested in installing on my trailer and I'm curious how and where you mounted the condensing unit.

 

[LeishaShannon]

Sorry about the blurry photo!

An 80x80x10mm aluminium frame "hangs" over the front edge of the camper and the indoor unit is directly behind the compressor. Its silent inside when running unless you turn on "powerful" mode , where a faint noise can be heard. A canvas cover stops bugs etc from entering the unit while driving.

 

[Maninga]

Very interesting. Got me considering adding one to my truck, we had a hot spell here lately where Heather's been asking a lot about it. My temperature tolerance range is about 5C to 45C, hers is 25C.

Will look at whether the condenser unit could replace one of the spare wheels.

 

[LeishaShannon]

You can pop in and check it out when you come to pickup your truck if you'd like, we're only 5mins from the airport

 

[bstory]

Do you actually bolt the compressor plate?

Hi,

Thanks for the pic and the info. Do you actually bolt the compressor when driving and if so, could you give some detail on where/how you bolt it? This looks a lot like the Mitsubishi we have for our house, even though the model you listed is not one sold in the US - Mitsubishi industries doesn't seem to do business here.

How long has your unit been installed and any estimate of how many miles it has traveled?

Thanks again!

 

[PGGRS]

I'll be using a Duotherm Cool Cat heat pump/AC in my ambulance. It's about the size of a small AC unit, but no real shell. It will go in one of the compartments, keeping the "white box" off the roof. It came out of a pop up trailer for that same reason. The Mfr. didn't want the weight on the lift mechanism. It's a 10K BTU cool & heat. More than enough for my build . I also am running a forced air furnace.The heat is AC in reverse, pulling any ambient heat from the outside air, so not as good as a furnace as you approach freezing temps. (Another reason it was in the tent trailer/don't see 'em out much in winter) Remember 110VAC...

 

[mhiscox]

I should have posted this earlier, but I forgot about the thread . . .

A while back, Kimberley Kamper came up with an off-road-capable split system installation for their upscale hard-side trailers, and now they have a model for tent campers you can buy separately. I'm not sure what relevance any of this might have for those of us not in the Antipodes (they're 240V systems, for one thing), but it's at least a proof-of-concept accomplishment.

http://www.kimberleykampers.com/off-road-camper-trailers-air-conditioning

BTW, Kimberley has done us all a good turn by posting a ton of useful information on their website, so if you click on the link, stay awhile to see what they offer in their "research books" and other resources.