During normal operation, the solar air collector gets started as soon as the sun shines. - The sun's rays will generate electricity in the solar cell, which will then get the fan to run. The fan will pull fresh air through the backplate and absorber felt - inside the solar panel. The air will be heated up and blown into the house.
On hot summer days, you will not need extra heating. Here you can turn off the system and thanks to SolarVenti patented backplate, the solar air collector is able to cool itself, so there is no overheating. SolarVenti is the only air collector on the world market that can cope with passive cooling even under extremely sunny climates. Other models have an extra fan to it. The Solarventi solar air heater is the only collector with such high certification to prove that it does what it says.
When you switch off the fan on a sunny day, the black absorber felt gets over 80 degrees Celcius and will then start a self cleaning proces drying out all germs etc. that might be in the felt.
The SV14, Sv20 and Sv30 solar air heaters are now manufactured with a solar cell placed in the backplate for several reasons.
1) you may inspect or replace the solar cell in a few minutes without special tools
2) the temperature of the solar cell will lower some 20 - 25 degrees under extreme warm conditions due to the thermal difference on the backplate.
3) the lower temperature of the solar cell gives a higher electric output for the fan.
This method is is a first for solar air heaters and never seen before - and is applied for patent. Later (autumn 2013).
See also SolarVenti Demo Video