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TheBlueprintof Water
Blueprint Pro · saves as a SystemWorked example · inputs locked

Tick what is in the line. Every device is solved at the flow it actually sees.

Operating Case

Enter your system parameters. Results update automatically.

A gauge at rest reads the supply's ceiling, not what you get when water moves. If you can, read it while a valve on this line is open.
psi

At rest. The result is a ceiling.

How Was It Read?A gauge at rest reads the supply's ceiling, not what you get when water moves. If you can, read it while a valve on this line is open.
Deliverable flow (ceiling)≈ 42.9 to 44.9 gpm 3 devices
Pressure at the delivery point. Atmospheric tank or open drain is 0. A pressurized deaerator is its operating pressure, typically 3 to 10 psig.
psig

0 for an open tank or drain.

Vertical rise from gauge to delivery point. Each 2.31 ft of rise costs 1 psi.
ft

Positive when the destination is higher.

Walk it and pace it; include vertical runs.
ft

Walk it; include vertical runs.

Read the marking or measure the circumference: OD is about circumference ÷ 3.14.

Sch 40 ID 1.61 in.

Sets the pipe roughness, the Hazen-Williams C factor.

C = 100.

FittingsCount them as you walk. Each is converted to equivalent feet of pipe.

9 counted, 28.5 ft equivalent; the run reads 148.5 ft.

4 ft
2 ft
2.7 ft
8 ft
0.9 ft
44 ft
13 ft
Devices in the LineTick what is in the line. Each device reveals the one or two things you can read off it; the model behind it is in the Formulas tab.

  • Does it have a drain funnel or vent port underneath? Yes is a reduced pressure assembly; no is a double check.

  • Cv

    Read the valve tag; it is often smaller than the line. Enter the submittal Cv if you have it; otherwise the typical by type and size. Using Cv 12, the typical.

  • psi

    Vessel diameter sets the rated flow at 10 gpm/ft². The rated drop defaults to 15 psi; the spec sheet may say otherwise.

Gauge CheckAt zero flow, gauges on the same line should agree; friction needs flow to exist. A gap beyond 1 psi plus the elevation between them is elevation or gauge error.

Click on any stream to learn more.

Every Device, at the Flow It Actually Sees

All quantities are live and update with your inputs.

Softener exceeded. 44.9 gpm through a vessel rated 31.4 gpm exceeds its design service rate. Expect elevated pressure drop and hardness leakage late in the run. Size the softener.

Operating Conditions
Supply
75.0 psi static
Pipe
1½ in Steel, 10 to 20 yr
Run
120 ft + 28.5 ft
Devices
3, 51.4 psi
Velocity
7.1 ft/s
Regulator
none

Key Results

Primary outputs and operational context based on your inputs.

This calculator estimates deliverable flow. Measuring beats estimating: if the line exists, open the valve that normally draws on it and clock the meter.

Deliverable Flow The root of the pressure budget with every device solved at that flow, at the design C and at 85% of it.

44.9 gpm

≈ 42.9 to 44.9 gpm (ceiling)

Estimated deliverable flow ≈ 42.9 to 44.9 gpm (ceiling: actual will be lower as the supply sags under flow).

Bare Pipe The same line with no devices: what the pipe alone would deliver.

99.8 gpm

no devices

54.9 gpm more than with the 3 devices in the line.

One Size Larger Every foot of the run one nominal size larger.

49.9 gpm

at 2 in

The same run and devices, every foot of pipe one nominal size up.

Low Estimate The low end of the range, the pipe at 85% of its design C.

42.9 gpm

at C × 0.85

A real pipe is rougher than its table row.

Softener Check Above 1.2 times the vessel's rated service flow, expect elevated pressure drop and hardness leakage late in the run.

31.4 gpm rated

44.9 gpm exceeds 1.2 × rated

Expect elevated ΔP and hardness leakage late in the run. Size the softener.

Pressure Budget by Name Of the pressure available at the solved flow, what each item spends, by name.
  • Pipe friction 15.2 psi, 20%
  • Backflow, reduced pressure 1½″ 8.8 psi, 12%
  • Control valve 1″ · Cv 12 14.0 psi, 19%
  • Softener 24″ 28.5 psi, 38%
  • Elevation 3.5 psi, 5%
  • Destination pressure 5.0 psi, 7%
  • Of 75.0 psi available at 44.9 gpm, 75.0 psi is spent getting water to the destination.