Complete supply and return circuit returning to the pump/source.

Source = pump / highest pressure.
End nodes are auto-detected: nodes with HX/coil components, or dead-end branches.

OD 60.3 mm ID 52.5 mm wall 3.9 mm

ASHRAE Fundamentals Ch.22 Table 1 (screwed fittings, by size) or Crane TP-410 (typical values, not size-adjusted)

Nodes are created automatically when drawing segments. Click a node on the canvas to interact, or manage here.

Heat-transfer and terminal equipment. Enter its design flow demand to distribute flow through the pipe network.

FCV/PRV are pressure-independent: within their rated range they self-regulate to hold a flow or downstream-pressure setpoint, so ΔP isn't a function of flow the way a fixed valve's is. Min. control ΔP above is the minimum differential the valve's datasheet requires to hold that setpoint (sometimes labelled "Δp min" or "starting pressure") — this is what the pump has to deliver, and is what's used in the pressure-drop calculation. Optionally record the valve's max. control ΔP rating below for your documentation.