Tips to remove scale?

we usually clean our rads with 10% vinegar in water. most recommend distilled water, but tap water should do if you dont have any around.

I find that just filling it halfway up with distilled/vinegar and vigorously shaking works pretty well. You can, however, set up a small loop with your pump, rad and a bucket of water or vinegar and just run it until you're satisfied with the results.

The only thing to be careful of is leaving the vinegar in the rad too long. Usually you want to rinse it with vinegar and immediately rinse with distilled/tap.

If the white vinegar doesn't get it out I have used full strength CLR in heater cores before. Just don't leave it in very long, shake it up well and rinse several times with plain water to get any residue out.

Unless it's really bad white vinegar should get it out. You can go with full strength if you don't leave it in to long. If it starts looking blueish when you pour it out you know your leaving it in to long, that's copper coming out with it when it gets that blueish tinge.

For normal cleaning just 10% white vinegar the rest distilled is fine. If you want to stay real safe just use multiple cleaning with that ratio till you get it all out.

thanks for the advice guys, I will pick up a couple jugs of white vinegar and distilled tomorrow when the stores reopen and see how it goes. happy thanksgiving!