I just thought I would let you know about the big difference between Apricus, Viessmann and Thermomax. I work for a company that distributes the Thermomax product in the Northwest (Seattle based) so my opinion is obviously a little biased but here are the facts:
Apricus makes an evacuated tube similar to the Thermomax and Viessmann but a big difference is how they seal the tube and maintain the vacuum inside. Apricus basically seals the tube with a glass to metal seal using a large metal disk. This will have increased thermal losses over a short time period. Yes, they put a 10-year warranty on their products but you would be lucky if the product held its vacuum for that long.
Another big difference is the type of glass that is used to make the tubes. Apricus uses a borosilicate glass and Thermomax uses a soda lime glass. Do some research. You will find that soda lime glass is a much better product. If for nothing else, your research will show that the process to make borosilicate glass creates a number of different pollutants. Is anyone proud of the environmental efforts of the Chinese? Doesn't it seem like a solar manufacturer should be taking every step possible to maintain a clean environment?
Thermomax and Viessmann have the exact same solar evacuated tube. They are both created to the same specifications. The biggest difference between these two brands is that Viessmann costs almost twice as much.
Thermomax tubes are guaranteed for 20-years, 10 years more than any other evacuated tube including Viessmann and Apricus. The difference is quality, quality, quality. There are Thermomax tubes out there right now that are still operational...from 30 years ago!
Last and certainly not least, Thermomax is the safest tube on the market. They have a patented self limiting device that if for any reason the tubes were to heat up above 275 degrees F they would shut themselves off from the manifold and prevent scalding of the liquid and system. No other company offers this on their tubes, including Apricus.
If you are interested in learning more then check out the website:www.kingspansolar.comwww.netzeroimpact.com