problem bleeding new boiler

drhvac

Hi,

Installed a new burnham boiler, and I am having a problem bleeding the system. There doesn't seem to be good water flow. I have a B&G fast fill reducing valve with the gate open, and usually the water would fly through, but not this time, it almost seems like it is bleeding a 12 psi, and by raising the gate, it is not increasing the pressure. The set screw on the reducing valve seems higher than usual, but when it fills the boiler, it does stop at 12 psi, so I thought the adjustment was accurate out of the box. I have the boiler feed piped in between the expansion tank, and spirovent.  The pressure back flow preventer is different than I usually use, but I doubt that is the problem. Any ideas, I would appreciate.

Thank you

Brad White

I have to ask

Is there still air in the system? (Do you still have a problem and if so, what?)



What kind of circuits, all baseboard for example? Can they be isolated for individual purging?



Any high point vents?

drhvac

there is a manifold

with 4 zones, 2 baseboard, and 2 radiant. Each zone is isolated, and water is flowing out of each circuit. I just concerned that with the gate open on the pressure reducing valve, there is not alot of pressure. That is about 50  psi flowing through there, and it is barely flowing out. I cleaned the screen on the valve, and it was a little dirty, but nothing substantial.

Brad White

If it is not broken,

don't fix it, would be my advice.



For example, you say 50 psi (I presume upstream of the reducing valve).  If there were air in the system, you would hear it. If it is silent (and the air separator is between the water entry point and the system), it sounds like it is doing its job.



Absent symptoms, what makes you think you have air in the system? May be all done.



If the gate arm is open and you are not increasing your system-side pressure, that just means that the arm is not forcing down the stem. But again, if you are not air-bound and have no noise, is there a problem?

clammy

check spriovent

Pull the element out of the spriovent i have had this happen to me a few times it seems some times the element will have a plastic cap on it (on the bottom of the element )and more then a few times it seemed to restrict the feed water also had it where the saftey valve was blowing off caused by the restriction of the plastic al on the end of the scruber element .Just pop it off and check it it's usually a quick job and it 's better then banging your head to fiqure it out that's what i did the first time it happened to me .Now i always check the spriovent before i install it to prevent the waste of time later .Hope this helps peace and good luck clammy

drhvac

thanks

thanks for your help guys. The problem was with the pressure reducing valve. I replaced the valve, and got plenty of flow afer that. Bled the system, and its been working fine for a couple of days now.