picking up air

gregchurchill

Weil McLain 4 section oil boiler. Standard piping, #30 expansion tank with push away manifold, 5 007's. First zone connected to 80 gallon indirect. 007 was replaced and keeps getting air. Bleed air out, not a big slug but enough small stuff to stop flow and have a no hot water call. Only four inch nipple off header to expansion tank, typical air scoop then hw circ. is first zone. Of course, worked fine before the circ failed.

Expansion tank and air vent issue? Seems all that new water has air not getting out of system. Seen it? Looking to fix it w/o being a parts changer

STEVEusaPA

Show us a picture of your near boiler piping-boiler, circs, expansion tank, air eliminator, feed...all in one pic.
Also what type of emitters?

Jamie Hall

And remember first principles: air can only get into a system -- once it's gotten out by purging and your air eliminator -- at a point where the system pressure is less than atmospheric. Such as, for example, a high point without enough static pressure, or at fittings approaching a pump which is pumping towards the expansion tank and sucking through a bunch of pipe and fittings.