We designed an air-cooled lamp holder for the photo-CDR reactors and designed all parts so that they could be obtained at low cost with access to a 3D printer. The design was based around the Kessil H150W 32 W lamp and we made a small insert adapter that could hold the Hepatochem lamp. Reflective surfaces in the cavity and a mirror incorporated into the base unit maximised the light intensity at the photo-CDR. The air-cooling, using a laboratory supply of compressed air, stabilised the temperature at 56 °C. We saw a reduction of >30 °C when compared to no compressed air, with lamp in close proximity to the photo-CDR (25 mm above the surface). We increased the distance of the lamp above the photo-CDR and showed and excellent correlation between distance and temperature with a maximum total distance of 50 mm in combination with air-cooling lowering the temperature below 40 °C. These findings were consistent with lowering the light intensity, in accordance with the Beer-Lambert law, resulting in lower temperatures. To investigate the lux at the photo-CDR would require further investigation however, we have established that we have excellent stabilisation of temperature using air-cooling. In addition, with a combination of air-cooling and distance using spacers, we were able to have control of a range of fixed temperatures and proportional light intensities. Control over both these parameters are essential to the optimisation of any given photocatalysed reaction. In combination with the air-cooler the photo-CDR allows additional control over other parameters that govern reaction kinetics by virtue of being a flow chemistry reactor.