In extractive analysis of process and flue gases, reliable and constant reduction of sample gas humidity is essential. Bühler Technologies offers a custom range of gas coolers based on Peltier and compressor technology. Process-based cooling temperature control guarantees maximum dew point stability. This allows highest quality industrial gas analysis. Bühler Technologies developed the extremely compact PC1 precooler to further increase the energy efficiency of the above main coolers. It is used as a small passive cooling level upstream from the main cooler. The PC1 very effectively uses the ambient air supplied by the fan as a coolant. In moderate ambient temperatures (up to 40 °C) it therefore allows the use of small, cost-effective main coolers. The intelligent gas path in the interchangeable precooling heat exchanger further ensures very low washout of watersoluble gases (e.g. SO2/complies with EN 15267). Optional PC1 heat exchangers with built-in acid meter connection (H3PO4) complete the concept.