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· PrimoPrep
Pre-treatment · Final stage · pH control

PrimoPrep

Mixed-metal compatibility prep. Controls the pH swing copper radiators introduce.

2ozThe whole bottle
32ozDI or distilled
72hCirculate, then flush
Buy PrimoPrep$7.99
1 : 16Never over-dilute
72 hoursMinimum run time
In the boxShips with Vue and True
2 yearsShelf life, unopened
01

What it does

Its job is the pH swing copper radiators cause. Mix it at 1 : 16, never weaker.

Bigger loop
A second bottle

Loop holds more than 32 oz? Mix another bottle at 1 : 16. Never stretch one.

72 hours
The full run time

Three full days of circulation. Normal use is fine.

Last stage
Right before coolant

After SysPrep or Reboot. Fill your coolant as soon as it is flushed.

02

Use it in five steps

  1. 1

    Leak-test first

    It runs three full days. Test on plain water first.

  2. 2

    Mix at 1 : 16

    2 oz into 32 oz of DI or distilled. A second bottle for bigger loops.

  3. 3

    Fill, bleed, run 72 h

    Tilt the case to clear air. Normal use is fine.

  4. 4

    Drain and flush

    Until the water runs clear with no foam.

  5. 5

    Fill with coolant, right away

    The loop is pH-stable now, not protected.

Download the prep card
03

What it works with, at a glance

Use with

  • PETG, flexible tubing, acrylicSafe on all of them.
  • Rubber seals, o-rings, plasticsSafe.
  • DI or distilled water32 oz per bottle.

Never with

  • Aluminum componentsNot compatible.
  • Stretching one bottleMix a second bottle at the same ratio instead.
  • Plain water after the flushFill your coolant straight away.
  • 2oz

    Per 32 oz

    A 1 : 16 ratio.

  • 72h

    Minimum run

    Then drain and flush clear.

  • 2yr

    Unopened

    Shelf life from purchase.

  • Stage 3

    In the sequence

    The last step before coolant.

04

The full story

A water-based pre-treatment that prepares a cooling loop for compatibility with modern high-performance coolants. Its main job is regulating the pH fluctuation caused by copper coming off radiators, the variable that quietly decides whether a mixed-metal loop stays stable. Ships in the box with True and Vue.

05

Other preps and treatments

PrimoChill

Keeping It Cool is the technical library of PrimoChill. Products ship from primochill.com.

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