Platinum RTDs (resistance temperature detectors) have been commonly used for temperature measurements for a long time in the building industry. In fact, most of the BAS companies use PT100 sensors. Why do the authorities have a preference for thermistors?

The Green Mark standard is performance-based and technology-neutral. BCA accepts any measurement system that can provide a long term end-to-end temperature measurement uncertainty of ± 0.05°C. In a typical chiller plant, temperature ranges from 0°C to 40°C, 10KΩ thermistors have been shown to offers good sensitivity to changes in temperature; whereas a relative change in resistance (temperature coefficient of resistance) in PT100 varies only slightly for the above temperature range.