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· Rad Clean — Full Kit
Radiator flush · Fittings included

Rad Clean — Full Kit

The same radiator flush, bundled with the fittings and funnel to run it.

½Half a bottle, 1 oz
32ozDistilled, RO or DI
1hFlip at 30 minutes
Buy the Rad Clean kit$14.99
In the box2 fittings, o-rings and a funnel
Up to 8Radiators per bottle
Reuse the batchDrain it into the next radiator
Never in a loopRadiators only, off the loop
01

Why radiators get their own flush

Brazing flux and solder debris ship inside every radiator. Three hot-water passes will never reach them.

Hot water first
Three passes

Shake 60 seconds in every axis, drain, repeat until clear.

Then Rad Clean
One hour

Fill completely, cap, shake, flip at 30 minutes.

Then SysPrep
On the first fill

The radiator is bare metal now. Condition it with the loop.

02

Use it in five steps

  1. 1

    Cap with the kit fittings

    The plastic fittings and o-rings in the box seal the ports.

  2. 2

    Three hot distilled passes

    A third full, shake 60 s in every axis, drain, repeat.

  3. 3

    Mix and fill

    Half a bottle into 32 oz of distilled. Fill the radiator completely.

  4. 4

    One hour, flip at 30 min

    Shake occasionally so both ends get contact.

  5. 5

    Drain, rinse twice, dry

    Then run SysPrep on the first fill.

Download the prep card
03

What it works with, at a glance

Use with

  • Radiators, on their ownOff the loop, never running in it.
  • Plastic fill-port capsWith o-rings.
  • Distilled, RO or DI water32 oz per half bottle.

Never with

  • Nickel-plated fittings or partsPlastic caps only while it works.
  • Aluminum partsNot compatible.
  • Inside a running loopRadiators only.
  • 1oz

    Per 32 oz

    Half the bottle.

  • 1h

    Run time

    Flip at the 30-minute mark.

  • 8

    Radiators

    Per bottle, reusing the batch.

  • Stage 1

    In the sequence

    Before the loop is assembled.

04

The full story

Identical concentrate and chemistry to standard Rad Clean, packaged with two plastic fittings and o-rings plus a threaded funnel, useful if your radiator does not already have PrimoChill-compatible fill ports to cap it with while it works. No gloves or goggles required. Safe on the internal metals found in radiators only.

05

Other preps and treatments

PrimoChill

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

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