Live Calculator

Hydronic Pipe Parameter Calculator

Solve for pipe size, pressure drop, or velocity · Copper Type B & Mild Steel Sch. 40 · Chilled, Hot & Condenser Water

01Water Type

6°C · ρ 999.8 kg/m³ · μ 1.307×10⁻³ Pa·s

02Pipe Material

ε Copper: 0.0015 mm · Steel: 0.046 mm

Step 2 — What do you want to find?

Water flow rate is always a required input

FIND

Pipe Size (DN)

Known: flow rate + max ΔP
Finds: minimum pipe DN & velocity

FIND

Pressure Drop

Known: flow rate + pipe DN
Finds: pressure drop & velocity

FIND

Velocity

Known: flow rate + pipe DN
Finds: velocity & pressure drop

Step 3 — Enter Known Values

Known: flow rate + max ΔP → Finds minimum pipe size

AWater Flow Rate FIXED

Litres per second ( L/s )

BMax Pressure Drop INPUT

Pascals per metre ( Pa/m )

Optional ConstraintOPTIONALLeave blank to ignore

CMax Velocity

Metres per second ( m/s ) · Pipe sized so velocity does not exceed this

Awaiting Input

Select a solve mode, enter values, then tap Calculate

Method: Darcy-Weisbach with Colebrook-White iteration (80 passes, converges to 10⁻¹&sup0;). Pipe IDs from AS1432 (Copper Type B) and ANSI B36.10 (Mild Steel Sch. 40). Fluid properties at design temperature: CHW 6°C, HW 60°C, CW 29.5°C. Velocity guideline 0.7–3.0 m/s. Results apply to straight pipe segments only. Guide only; does not replace professional engineering judgement.