I got my control unit burnt through the sensor cable which was on the mirrors at the rooftop. The safety on the controller was intact and we saw circuits burnt after the safety and near the sensor pins. After that i decided that i need further protection since the anti-lightning installation on the rooftop proved to be not enough.
Mounting it under the mirrors with a bit of drilling and a few nuts n bolts as well as attaching the cables from the sensor in the mirror to SP10 and from SP10 to my controller in the house was pretty easy.
The controller after connecting everything showed the temperatures as before the installation, so i guess it worked fine. All that remains is to be weather and lightning tested to see if it works.
The only question i did not understand in the circuit of the device is why not put a safety that can be changed if the existing one gets burnt by a lightning over-voltage. I guess if the rest of the circuit is not melted, and provided that you can get your hands on the same chip/ safety type, you can un-solder it and re-solder the new one. But this could be avoided using a removable type, where you could just change a safety and not the whole device.