Flow Temperature Calculator
Why Flow Temperature Matters
Flow temperature is the single biggest lever for:
- Heat pump efficiency
- Running cost
- Comfort and radiator performance
Add2Rad helps radiators deliver more useful heat at lower flow temperatures, allowing systems to run cooler without sacrificing comfort.
How To Use This Calculator
Use the calculator to get a recommended flow temperature band.
You will need:
- Estimated heat loss
- Radiator or UFH emitter type
- System type (heat pump or boiler)
The calculator will suggest:
- Mild-weather flow range
- Typical winter range
- Cold-snap range
Rule-of-Thumb Ranges
For systems with Add2Rad applied:
- Mild day (10–12 °C): 35–40 °C
- Typical winter day (3–7 °C): 40–45 °C
- Cold snap (<0 °C): 45–50 °C