Bleeding multiple zones question

Joseph_4

I have a basic question about bleeding zones from the boiler room. I've been taught that normal system pressure is 12 lbs, when its heated it rises to about 18 to 20 lbs.I've also been taught to hook up a hose to the hose bib of each zone and close ball valve, open hose bib and lift feeder up to fast fill postion (city street pressure is say 60lbs)  to force out bubbles which i see coming from other end of my hose which i submerge under the water at the bottom of  a 5 gallon bucket. when u see no more bubbles, the zone is bled. " They tell me, keep your eye on the pressure gauge though. because if on fast fill too long the relief valve will pop b/c will go past 25 lbs. My question is, when I do this to multiple zones and am rid of my bubbles on say 4 zones, the pressure in boiler may be up to 22 lbs. If i then heat boiler up wont it go past 25 lbs and relief valve will pop? How do I get my system back down to 12 lbs with no bubbles anywhere so i can turn boiler on without  starting it with too high a pressure?

Timco

fast fill

Close the fast fill with hose still attached and drain the system back down to 12# cold for 1 story, 15# cold for 2-3 story. If you drain out too much, the fill will refill it to the set pressure.



Tim