Thanks again!

I think I will wait for a couple of days for the air to separate from the water and the noises to start back up again before I try.

I have a couple of Q's on the "technique":
- Should I do this when the re-circ pump is off?
- Does it matter what the water temperature reads?

Also, my system is currently smack on 15 psi so don't foresee an issue there.