Auto Balancing Valves

Radiator output (Watts)

If you do not know the output of the radiator, you can try my radiator estimator....

Desired ΔT (°C)

Specific Heat Capacity (kJ/kg/°C)

Required flow across the radiator = l/min

Drayton/IMI AutoBalance Valve setting

Required values are potentially outside the performance ability of the current range of these auto-balancing valves.

Danfoss "Dynamic" Valve setting

Required values are potentially outside the performance ability of the current range of these auto-balancing valves.

Further information on these valves is available from the manufacturer websites:

↪ Drayton Controls
↪ IMI Controls
↪ Danfoss

This calculator expands on the data provided within the product leaflets and is only relevant for the latest "auto balancing" valves which often display a setting option between 1 & 15 (Or 1-7 on Danfoss valves).

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Updated 01 February 2026 in engineer tools.