I'm interested in your project, and am wondering if you are embarking on a similar project to mine. I'm installing a couple of temp probes (thermistors) inside a piece of plastic trunking 50mm square and approx 600mm long. This will be ventilated by a small 40mm squrre fan mounted in one end and the whole tube will be built into a wall separating my garage/workshop from the conservatory. The idea is that the probes will be installed within the trunking and measure air temperature within the conservatory, the portion of the trunking within the conservatory will be sheilded by reflective aluminised polyester and the fan and the control gear will be in the workshop area. The high solar gain within the conservatory would normally introduce errors to the accuracy of measurement and to achieve adequate shielding of the sensor it must be enclosed in some kind of screen but of course the more effective the sheilding the more difficult it is to expose the sensor to the air whose temperature is to be measured., hence the fan, which will draw air across the sensors and will also minimize the self heating effects of the thermistors.
The control gear will adjust motorised roof vents in the conservatory and will also serve to elecrically heat and enable frost free conditions in winter.
Please Excuse my ramblings, It's raining C&Ds here :-( Regards
Don