- Tap water: The permanent operating temperature ranges from 0°C to 70°C at a maximum permanent operating pressure of 10 bar. The short-term malfunction temperature is 95°C for a period of 100 hours in the operating life time.- Underfloor heating and low tempertaure radiators- Heating: The permanent operating temperature ranges up to 90°C at a maximum permanent opereting pressure of 6 bar. The short-term malfunction temperature is 100°C for a period of 100 hours in the operating life time.