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TheBlueprintof Water

Set the loop and the target. Read what to drain and what to add.

Operating Case

Enter your system parameters. Results update automatically.

Total loop volume. Do not know it? Measure it in the System Volume Calculator.
gal

Total loop volume. Do not know it? Measure it in the System Volume Calculator.

Glycol TypePropylene glycol for anything near food, potable water, schools, hospitals; ethylene glycol only where toxicity is acceptable. Use inhibited HVAC grade glycol, never automotive antifreeze.
Freeze point today, at 0.0%32 °F propylene glycol
Refractometer reading, set to the right glycol scale. A new or water only loop is 0.
%

% by volume, off the refractometer. 0 to 70.

Enter either a percent by volume or a freeze point; the room shows the other.
%

Holds 8 °F.

What is in the drum. Premix changes the drain and add math a lot.
%

Neat, or the 50 and 30 premixes.

How Will You Add It?A full loop cannot accept more fluid; you drain X and add X of concentrate. If the loop has room (drained down, expansion capacity), you can add without draining.

A full loop cannot accept more fluid. You drain X and add X of the drum, and the volume stays what it was.

Click on any stream to learn more.

Freeze Protection by Displacement

All quantities are live and update with your inputs.

Operating Conditions
Fluid
PG, inhibited
Loop
1,000 gal
Today
0.0%
Target
30.0%
Drum
100.0%
Method
Drain and replace

Key Results

Primary outputs and operational context based on your inputs.

Freeze point is the first ice crystals; burst protection is the fluid becoming slush that expands too little to split pipe. Choose the target by which failure you are preventing.

Drain and Add The gallons that move. On the drain path the same volume leaves and returns; on the add path the loop grows by it.

300.0 gal

of 100.0% PG

Drain 300.0 gal, add 300.0 gal of 100.0% PG.

Final Mixture The blend the dose lands on, checked from what stayed and what went in.

30.0 % PG

1,000 gal in the loop

Now treat the loop for corrosion.

Freeze Point First ice crystals at the target blend, off the manufacturer's curve.

8 °F

at 30.0% PG

First ice crystals.

Burst Protection The fluid becomes slush that expands too little to split pipe. Read as the table row at or below the target.

−13 °F

pipe survives to

Slush that expands too little to split pipe.

Freeze Point Today The protection in the loop right now, at the refractometer reading.

32 °F

at 0.0% PG

What the loop holds before the dose.

Concentrate Price Delivered price of the concentrate per gallon. Water costs nothing here.
$
per gal
Concentrate Cost$7,500

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