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keepingit.cool

Cooling,
documented.

Dilution, run times, prep order and service intervals for every PrimoChill fluid and kit, from the people who have mixed it for 25 years.

Not sure which fluid you need?

Two questions, new build or existing loop and showcase or daily driver, and you get the fluid and the prep order.

Not sure which prep you need?

Two questions, what you are prepping and whether you want the kit, and you get the bottles in order with the dilution for each.

The loop

Every bottle has a place in the circuit.

Coolant leaves the reservoir, passes through the blocks, sheds heat at the radiator and returns. Each prep treats a different part of that path, so the order matters.

Fluid colour
Sky Blue SX
Water-cooling loop topology and prep coverageThe pump drives coolant up to the radiator, where it sheds heat, then across to the CPU block, then the GPU block, then down into the reservoir, which feeds the pump again. Rad Clean treats the radiator on its own before assembly, for a one hour dwell. SysPrep and PrimoPrep are both circulated through the whole loop. SysPrep first, for twelve to twenty-four hours, to lift manufacturing debris, then PrimoPrep for seventy-two hours to settle the pH ahead of the permanent fill.PumpCPU blockGPU blockReservoirSysPrep · 48 hwhole loop, lifts manufacturing debrisPrimoPrep · 72 hwhole loop, settles pH before the fillRadiatorRad Clean1 hour
SysPrepWhole loop · circulate 48 h

The everyday whole-loop pre-treatment. 15 ml into one US gallon of DI or distilled water, circulated for 48 hours, then drained and rinsed. It clears what the blocks, tubing and fittings carry out of manufacturing so your coolant is not the thing cleaning them.

Before the first fill

Nothing in this loop shipped clean.

Machining swarf in the block fins, flux and solder debris in the radiator, bending lubricant on the tube. Your coolant meets all of it on day one, and gets the blame when the loop clouds at week three.

Assembled loop with clear acrylic blocks and brass fittings
Machining swarfBlocks

A 0.25 mm fin channel does not need much to block. Open a new block and look before it ever sees fluid.

Brazing fluxRadiators

Sits in the tube ends from the factory. The number one source of blocked block fins in a first build.

PlasticiserSoft tubing

Leaches out of clear flexible tube over weeks. This is the clouding people see at two to six months.

Bending lubricantHardline

Handling oil and bending lube go straight into the coolant on day one unless the tube is wiped first.

Drain the first flush into a clear bucket and hold it against something white. That is what was about to go through your blocks.

The fluid line

Eight bottles. Four different forms.

Ready to use, concentrate, additive, base. Pick the form before the colour: a concentrate needs a gallon of DI water, and an additive needs a gallon of DI water and adds no colour.

Start here
New to the game

Never built a loop before?

16 guides, from the first radiator flush to the annual service. Tools listed first, nothing assumed.

Ask us anything

Send us a photo and a parts list.

We will tell you what the residue is and which bottle fixes it, usually within 48 hours.

Answered already

PrimoChill

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

Guides
Fluids

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