Reconditioning an existing system: Rad Clean, Reboot, PrimoPrep
This is the complete protocol for reviving a loop that has already run coolant, after a fluid swap, a build that sat too long, or a loop you bought used and want to trust. Three layers, in order: Rad Clean strips flux and oxidation from the radiators, System Reboot deep-cleans the whole loop of old dye and biological buildup, and PrimoPrep chemically re-stabilizes the pH before your next fill. Do not rush the soak or circulation times, cutting them short leaves old residue only partly neutralized.
PrimoChill is not liable for hardware damage incurred during the cleaning process; use at your own risk.
Read the whole guide first
This is a multi-day sequence with three different chemistries in it. Read to the end before draining anything, and lay out every bottle where you can see it.
Running a step out of order here is worse than in a fresh build, you are working on top of years of accumulated residue, and undoing a mistake means starting a stage over.
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Keeping It Cool is the technical library of PrimoChill. Products ship from primochill.com.
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