Does it help to put a main vent on a pipe right next to the boiler

acl10

Does it help to put a main vent on a pipe right next to the boiler .

Jamie Hall

Depends on the pipe. If it's a dry return coming back to the boiler and dropping, then yes -- and it this is a two pipe system it not only helps, it's required for the system to operate properly.

However, if it's a steam main, then no -- it will do no good at all. Steam will hit it almost immediately, and it will close. Might as well be a pipe plug.

acl10

Its the return pipe from the basement baseboard heating that goes back into the boiler

Jamie Hall

Then yes. How else will the air get out of the baseboards? Assuming the baseboards are steam, that is. If they're a hot water loop from the boiler -- you do need to be able to bleed air out of them, like any other hot water system.

JUGHNE

See the pictures in Dave0176 posting on boiler replacement.
You and I both posted there minutes ago.

acl10

The problem is that If I put a steam vent on the pipe water comes out when the baseboard goes on so I put a Taco vent on, it holds the water but when the baseboard isnt on a little steam comes out.

Jamie Hall

If this is a hot water loop -- and I'm beginning to think that it is, though you haven't said so -- then it doesn't need a vent at all. What it needs is a way to bleed air at the highest point of the loop. If that highest point is above the water line in the boiler, however, you don't really even need that. What you must do in that situation, is to arrange the pump so that you are pumping from the boiler into the loop. That will purge, more or less well, the loop the first time the pump is turned on. After that, assuming that the return is below the water line as well, the loop should stay full of water.

acl10

New vent near boiler stopped the water hammer on startup.