Engerwitzdorf, Austria The CO2 Transmitter Series EE85 for HVAC from E+E Elektronik has been designed for accurate measurement of CO2 levels in heating, ventilation and air conditioning (HVAC) applications. It is available for measuring ranges of 0 to 2000ppm and 0 to 5000ppm. Its compact design allows easy installation in ventilation channels. CO2 detection is based on the accurate, non-dispersive infrared technology (NDIR). Aging effects are compensated by a patented auto-calibration procedure, which is the basis for the outstanding long-term stability of the series. Due to a small differential pressure created by a special construction of the sampling head, a small stream of air from the duct is led to the CO2 sensing cell and back into the duct. The air diffuses into the CO2 sensing cell through a diaphragm. The closed loop air stream and the diaphragm protect the CO2 sensing cell from pollution and by this avoid pollution related errors. Demand controlled ventilation based on CO2 minimizes fresh air to re-circulated air ratio which has a relevant impact on energy saving. E+E Elektronik GmbH , Engerwitzdorf, Austria. www.epluse.at.