Webasto cooling system???

I've wondered for a couple years if an efficient rooftop unit could be run for the 10 - 12 hr duration of most overnight breaks on cool with a bank of 4 AGM batteries? I'm sure someone cruising through here will know the math.

For my needs cooling is much more important than heating. I see that the euro units get strong reviews for heating. Do they cool well also?

 

Read the link about the units they are using in Europe. I'd sure like to know more about them - how they work, where to get them, what they cost? Particularly what is meant when you talk about using "gas"? Are they propane fired for heating and cooling like an RV refrigerator?

 

Ahh gas is refrigerant like in your a/c , it needs to be topped up every few years, waeco are called domestic in the US and I don't 'think' there's much difference between ours and your roof mounted versions only we don't use a generator to power them, they are a simple compressor a/c unit like you'd have at home only really compact and built to take a battering, ours run off the trucks own batteries and will run for up to 30hrs without restarting the truck, when battery power gets low it switches off so as not to run your batteries down so much you have to jump start. They cost roughly $2500, I don't know why they don't sell a 12v unit on the US cos they use them in OZ on American rigs.

There is also water cooler versions like VIESA, they do sell in north America , they work very well but once you go over about 35 C they aren't too efficient , when the water gets hot in the tank they lose alot of cooling ability, those cost about 1100-1300 dollars

Both types are silent and except for occasional gassing of the compressor units virtually maintenance free.

Neither of these units have the ability to heat, a diesel fired cab and engine block heater comes as standard in almost all trucks here so I honestly can't tell you how much those cost.

 

If these units run for 30 plus hours on battery power and cost $2,500 I can't believe that every truck in the country doesn't have one! I gotta research this further.

 

Every truck here does, that's why I can't believe the cost or demad for APU's

What I should also point out is our trucks run on 24volt, it will take someone more educated than me to figure out how much of a difference that makes but I know these units are popular in Australia on 12v American rigs, if they work there they will work anywhere!

 

Actually I should specify 30 hrs is the max I got out of one before the beeper before shut down, so it's not 30 + it's approx 30 hrs, but thats on 24volt!

 

Hay Scania, ever see one of those cooling systems on a day cab? I do lots of idling around asphalt plants in the summer. 70% idle time on my ECM . Might check them out.

 

Yeah I know a guy with one on a tipper, he bought the truck secondhand and it had no aircon

 

Webasto sell a unit here but it has very poor cooling, waeco is called ' domestic' over there , They are really good, I can't find an American website for them, I found one for viesa in Canada, these make water evap units, not great in desert heat(35deg celcius +) cos they get hot then the water gets hot and that reduces coolin ability, however there is an interior model there also, I've never used one but it should eliminate that problem but I've never tried that particular one, I believe that viesa is coming out with a compressor model soon. Also viesa are very cheap and trouble free! http://www.viesa.ca/

these units are very popular on Australia maybe an Australian driver can tell you how they cope in the desert heat and maybe useful tips for the water evap models like where to put the water tank so it works better, here in euro land we are limited by space so choices on installing a tank are limited,