I'm after some advice if that's ok. I've installed a couple of Navitron evacuated tube collectors with TDC3 controllers in our past couple of properties which both worked well.
We're about to have a small pellet boiler installed and will have a solar coil in the tank. I bought an old Thermomax collector second hand for £50 from someone who was renovating a house and having dormers installed

I also managed to salvage an old SMT100 controller, thermomax pump and expansion vessel. The collector has a temperature sensor but I realised afterwards that I didn't salvage the temperature sensor from the HW cylinder..
So I wondered if anyone had experience with this collector/controller, any advice on where to get a spare sensor or two for the cylinder and any advice on a standard plumbing setup ?
Many thanks!