In this communication we report our investigations into the control and monitoring of temperature in a 3D printed circular disk reactor (CDR) for continuous flow photochemistry using datalogging via a Raspberry Pi microprocessor. A lamp base and holder were designed and realised using 3D printing to enable efficient monitoring of temperature using a temperature probe and the photo-CDR was cooled using a constant controlled flow of compressed air. We demonstrated that temperature gains under commercial LED light sources are significant and that the design of our suitably designed low-cost air-cooled holder could control and stabilise the temperature of the photo-CDR over sustained time-periods.