The pipe diameter must be selected based on the required flow rate and the permissible pressure drop.
Water flow rate
The required flow rate depends on the unit's thermal power and the design flow-return ΔT.
Water velocity
Excessive velocity increases noise and pressure losses. A pipe diameter that is too small makes it difficult for the circulator to achieve the required flow rate.
Correct selection
The final diameter must be determined through hydraulic calculation and the manufacturer's data, not solely by nominal power.
