OK I did a search and nothing really came up. I read on some post on the net that these vents really let the heat through. Can anyone give me feed back on their windows and vents pluses and minuses. For instance is bigger better or should one stay small? so feed back on size, heat, blinds & flyscreens.
-- Edited by iana on Saturday 2nd of May 2015 07:30:03 PM
Ian. There was a post not long ago about roof windows generally and most agreed (me included) that with the light comes a lot of heat. Im not familiar with midi model, but my van has two Dometic roof windows. They have 2 slides in them - one is insect netting and the other is like a type of shade cloth so that wind can get through them so they don't get damaged.
Yes, on a hot day, they let buckets of heat through and the shade cloth is not 100% obviously.
The previous post was people who had come up with various ways of temporarily blocking out the sun/heat from using cardboard which you just pushed in there to corflute and other insulation materials.
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Cheers Bruce
The amazing things you see when nomading Australia
We did lots of research re ceiling hatches/vents , in previous vans we have had an assortment of types and some have been problematic.
Our findings were for basic simplicity and ease of use the standard 4 seasons takes some beating, the newer plastic one's did have issues with sealing but that has now been overcome by correct installation.
We now have one of these and it has been trouble free after being re fitted correctly. (a small leak developed after around 6 months, but was re fitted with new seal and sealant) It has now been fine for 2 1/2 years full time use.
The large Dometic variety are like living under a greenhouse roof, they suck in heat and transfer it to the van internally, never have one again ! also if damaged cost an arm and a leg, as most Dometic stuff does.
Smaller Dometic style vents, the internal fly screen became damaged easily and we lost one top when it was inadvertently left open, yes operator error and expensive to replace. This was in a past van.
We now have, as said, a new 4 seasons in the living area and a Fantastic hatch over the bed, both work well as they should, the Fantastic is great on a warm night to reverse and bring in a cool breeze over you.
We have additional external hatch covers that allow the hatches to be left open in rain or while travelling with no leaks or issues at all. Cost $47 each from the USA delivered from Amazon. They are called Maxxair 11 and are brilliant.
We also have 2 Caraframo fans either side of the bed, but rarely use them as the Fantastic hatch is quiet and efficient and uses the same power as the Caraframo's.
After 4 previous vans we feel we have found what works for us with reliability and no hassles.
Thanks guys, yes we can't have it both ways, the foam sandwich hull makes a good insulated unit, then we spoil it all by installing big vents and windows. Just trying to get a grip on the best compromise.
A little research discloses that heat travels by convection, conduction and radiation. Double glazing stops the conduction and the convection currents, but not the radiation, that passes straight through as ultra-violet and infra red heat. Yeh! I know there's all sorts of variances with different wave lengths, but in general that is what happens. The double glazing would stop cold rather than heat. Cold is all convection and conduction. I think putting up a reflective blind over the window will help reduce the heat it lets through. Like what we put in the cars windscreen.
