Air con

[InaPickle]

I’m looking for advice with regard to the best place to install air con on the roof. We have a 6 meter Knaus van with a sliding side personnel door. We also live in southern Spain where summer temperatures can easily top 40 degrees.

Can anybody with any experience advise whether they would site the air con in the roof light at the front of the van or over the fixed bed in the back of the van. Which would be the best place to reduce the temperature throughout the van?

I have been comparing Truma and Dometic and would appreciate if anyone has experience of both to advise which they preferred.

[StuartO]

You need to be realistic about the limited cooling capacity of roof-mounted air con and the noise they make while operating. Our dash air con is very effective when we are driving but the roof aircon can only deliver about 1.5 kw of cooling and that only manages to reduce the temperature inside the MH by two or three degrees when it’s very hot outside. My wife has always found it too noisy to be tolerated overnight anyway so we make do with open windows and battery-powered fans on the bedside table. The power limit on the EHU is another consideration, so for example you probably couldn’t operate two roof air cons simultaneously from the EHU on most campsites. I doubt whether I would bother with roof aircon on our next MH but if I did, I would position it for optimum daytime effect.

[paulmold]

I have a Dometic air con on the roof. It runs obviously only when on hook up but for air con to work properly you need to shut all doors and windows as you do for air con in a car. Mine takes over an hour to reduce temp by 2 degrees. It is certainly too noisy to use overnight. I'm thinking of having it removed and replaced by a another roof light (that will make it three) as I'm sure I would get better cooling from 3 open rooflights. It was on the van when we bought it, it was standard spec, I would never have had it fitted myself.

[Laurence]

Andrea, we had the Truma Aventa Comfort on our previous motorhome, and we have the Dometic Freshjet 2200 on our motorhome now. We found the Truma brilliant, but because we downsized we went for the Dometic, which is slightly smaller inside and outside, for almost the same specifications.

 

The bottom line is that we wish we had gone with the Truma again. In comparison to the Truma, we find the Dometic lass effective (even in a smaller motorhome), more noisy, and when the Dometic compressor kicks in and out, you get a small shake of the van. The Truma never did this, but I think it has a slightly different technology which smooths out the cyclic effect of the airflow. The Truma also has a night setting to reduce noise.

 

With the Truma on, you could stand outside the motorhome and not hear it. With the Dometic, its not too bad, but it is slightly noisier. We also found the Truma more effective on producing heat, but we rarely used that function, and also the air vents were more adjustable.

 

Just personal experience, for what it is worth. Hope this helps.

 

Regards,

[InaPickle]

Thank you Laurence, that’s really helpful.

[flyboyprowler]

Just a thought, but do check your payload before fitting as these units are not that light!

[Archiesgrandad]

We removed the aircon from our last van because it was too noisy and not terribly efficient, most of all it was extremely heavy, and I did not think that it was a good idea to have some 50 kilos perched on the back of the of the roof, way behind the rear axle so there was a considerable overhang and it took a significant part of our payload.

 

AGD

[dicksob]

Hi, we have the fresh light 2200 mounted in the middle of the van and directing cold air to the back and front. Unlike a number of others we wouldn’t be without it, using it all over Europe and in uk. In Spain last year it would lower the temperature from 40 degrees plus in the early evening to mid 20’s by bedtime, which we thought was great. Like others we switch it off overnight.

Bill

[Guest rael]

Would not be without it. Have had it on 4 vans and a caravan. Will be getting it installed on our new van ready for the summer. I'm amazed to hear that others have not had good experiences. As we always go to hot places in the summer (Croatia, Greece, Italy etc) its been essential. You must, however, ensure that you get the correct size unit for your van. They reckon for a 6m like yours (and my new one) then a 1700 is ok but I'd be tempted to go to a 2000-2200. We've had no trouble getting the inside temp down to the low 20s even when its 35 plus outside, on all our previous motorhomes. Naturally you need to ensure windows are closed, blind down etc. We usually have thermal blinds on the inside of the windscreen and another cover on the outside if in direct sunlight. The noise can be an issue but we don't really notice it. The trick is to leave it on, if possible, rather than turning it off in the daytime. We've always gone for Dometic, but looking at the previous comments, might give the Truma a go. I was put of it last time by the dealer (in Germany). In terms of where to mount it, I'll probably go for the rear skylight above the fixed bed. Mid van would probably be better but, if its a panel van (which it sounds like it is) I think cutting a hole would be more difficult than on a GRP roof. You also have the issue of how much the unit protrudes into the van and if its going to get in the way of the bathroom door or cupboard doors. I'd also check the weight. I can't see any that weigh 50 kg, nearest is the Dometic 3200 (37KG), you won't need that unless you want frostbite. Most of the other units come in between 27-30KG

[thebishbus]

I removed our Dometic roof air con ( 39 kg on the roof ?) .Sold it on E-bay £400. It was too noisy at night , Not worth using in the daytime as we like our windows open. It drew 4 amps and would trip some hook up's when abroad. Replaced it and another roof vent with two Fiamma Turbo Vents, very good at moving air through the van and quiet enough on slow speed to use at night.

Brian B.