Danfoss Heat Meters
Danfoss heat meters are ultrasonic energy meters that measure the heating (and, depending on the model, cooling) energy used by a flat or a building. Each meter has a calculator, an ultrasonic flow sensor with no moving parts and a pair of temperature sensors. This page lists the residential SonoSafe 10 and SonoSelect, the commercial SonoMeter 40 and, for large plants, the Supercal 5 calculator with SONO 3500CT flow sensors.
The most common size in flats is DN20; the range covers threaded DN20–DN40 meters, flanged meters from DN50 and flow sensors up to DN600 for large plants.