Dometic rooftop aircon unit use and feedback

[AndrewCook680]

Hi
I’ve been trying out the 680 factory fitted roof aircon unit last couple days with van at home on driveway.
First day I didn’t put screen covers on, yesterday I fitted them about 11.30am when van was already over 30degC inside and it was 25 outside.

I closed all blinds on sunny side of the van.
I found after a few hours of full fan speed and aircon set to 16DegC it was 21 degrees in van at around bed area in back and 25 in table sitting area. I had hoped it would be cooler. But guess I should have put screen covers on earlier and indium grey paint doesn’t help either
Guess great whites get cooler inside

What are others experiences of the aircon and getting it cooler in front part of van ?

 

[GordonH]

We haven't run ours yet this year but last year in France when the temps were in the mid 30s the AC cooled the van down pretty quickly., less than an hour to take it to 21C. Blinds all closed, heat gain through the windows is huge. Ours is a 600 but can’t imagine its that different.

 

[AndrewCook680]

We haven't run ours yet this year but last year in France when the temps were in the mid 30s the AC cooled the van down pretty quickly., less than an hour to take it to 21C. Blinds all closed, heat gain through the windows is huge. Ours is a 600 but can’t imagine its that different.

Was that 21 in sitting area at front ?
We have 2 extra windows in 680 i suppose and a bit more volume to cool

 

[GordonH]

21C according to the van control panel temperature sensor which is above the rear bench seat. I guess there will be lots of heat gain through those side windows with the blinds open and still a fair amount with them closed if the sun is directly on them. To be fair our experience with the AC tends to be biased towards the evening and thats likely quite different as there is no solar heat gain once the sun has set. We used it a lot last year in France but only once or twice in the UK. I expect we will shortly be putting it to test again in Spain (heading that way this weekend). We are pretty well always outside during the day and don’t run the AC then We tend to put it on an hour or so before we go to bed, set to 18C, with all doors & windows etc shut & it cools the interior down pretty quickly. Once we go to bed we turn it to ‘fan only’ by setting it to manual cool, fan on & the temp at 22 ish, that way the compressor only kicks in occasionally. If you’ve not experienced sleeping with the AC on - fan is pretty quiet & gives a pleasant cooling breeze, when the compressor starts up in it shakes the van, not terribly but a bit like in an aircraft hitting some mild turbulence for a second or so. It will wake a light sleeper.

 

[AndrewCook680]

Thanks for feedback Gordon.
I had blinds closed, but van was facing East-west so while wide fully exposed to sun all day. If away camping we would probs have some shade from trees in a campsite or park van end on to the sun to minimise solar heat gain.

 

[AndrewCook680]

I also put a sheet of silver foil backed bubble wrap into front skylight which helped to reflect sun better than the blind

 

[GordonH]

Ive just run mine to see if I could give you any more data points - after 15 mins exit air from the a/c was 9.5C. Temp of area above bed was 22.5C. Fan on full, temp of a/c set to 18C, Cooling - Manual.

 

[AndrewCook680]

Thanks for that - usefull info - I will do more tests and measure outlet temp

 

[The Yorkshireman]

Here’s our low budget air con £20 from Amazon

 

[AndrewCook680]

Ive just run mine to see if I could give you any more data points - after 15 mins exit air from the a/c was 9.5C. Temp of area above bed was 22.5C. Fan on full, temp of a/c set to 18C, Cooling - Manual.

Tested this evening and AC unit exit temp down to 6degC when a/c set to 16DegC and got down to 19 above bed. So seems to be working OK just expecting too much in middle of day in full sun.
I also vented van Better this time first with doors and windows open to expel more hot air before putting ac in cooling mode

 

[flying banana]

Unfortunately most aircons can only cool so far below ambient air. So you reading's sound about right to me.

 

[GordonH]

Tested this evening and AC unit exit temp down to 6degC when a/c set to 16DegC and got down to 19 above bed. So seems to be working OK just expecting too much in middle of day in full sun.
I also vented van Better this time first with doors and windows open to expel more hot air before putting ac in cooling mode

Yes, looks pro-rata to my reading - both a 13C reduction inlet to outlet.

 

[Waldo]

is the roof aircon also working when driving? is it a good option to install aftermarket in a Grand Cali which has no Climatronic?

 

[GordonH]

No. Just on hookup (shore power). The GC has manual ac and that is effective.