Last Spring I was having trouble with air in the lines. each morning when the thermostats kicked in I would be reminded of the problem when I would awake to the sound of air banging though the system. Being the procrastinator that I am, I forgot about the problem when it warmed up outside. Well, now I have to get it fixed as it's cooling off outside.

I have bleeders at every baseboard unit. If I try to manually bleed them it doesn't seem that there is much system pressure there. This leads me to believe I might have a problem with the (don't know the name) one way valve that lets water in from the main water line or a problem with the pressure tank or both. (I can bleed all the air out of the system manually and within a day or 2 it's back).
There is a lock nut adjustment on top of the one way valve so I assume I can adjust it to fix the problem? Add air to the air tank with the valve stem on the bottom of the unit? I haven't touched either part yet, just thought I would get some advice before I do.
I have a couple bleeder valves I'll have to replace as they have been leaking awhile and are very corroded. It seems to me there isn't enough system pressure to close the bleeder valve completely, letting them seep slightly. Could this be what's happening or do I have other issues? The furnace & system is about 6-7 yrs. old. Haven't had any real problems until last spring. I don't have a pressure gauge to check system pressure, but I can find one if that is needed.
Thanks in advance for any pointers.

I don't know if this means anything, but the air in the system seems to be in one spot. What I mean is, I can hear air in the lines...then it goes away even though the pump is still pumping water....then comes back again. It's like the air bubbles are concentrated in one spot and that spot circulates through the system. Could that mean I have a problem in one spot (one way valve) and that's why the "air in the lines" noise comes & goes like it's making laps in the system?

 

Bump to the top. Any guesses?

 

I don't like guessing ... I like to analyze ...

There's no pressure gauge on the boiler ?

You've gotta have a pressure gauge ... you need to know that first, in order to troubleshoot. You can pick up fittings and make an adapter for one of the hose bibs with a 0-30 (or 50) PSI gauge. Screw it on the drain, open drain, read pressure.

They sell them pre-made at HD and Lowes for about $10 or so, but the gauge is a 0-200 PSI job intended for water systems. You can't barely see 10 PSI on that gauge. You could buy one of those for the fittings, then go to a supply store and pick up a gauge and replace the one that it comes with.

Is there at least a temp gauge ?

What make/model is the boiler ?

I think we need pictures ... lots of them ... show us the entire system ... with close-ups of things you think there may be issue with, such as the bleeder valves you mentioned... make sure there are one or two shots far enough back to see the 'big picture' ... upload to a free account at Image hosting, free photo sharing & video sharing at Photobucket and provide links to the pics here ...

 

Another thought ... be glad the air is moving around in the system... that means it's not 'stuck' somewhere, stopping the flow.

Is there an 'air scoop', 'separator', 'scrubber', (whatever you want to call it) on the system ? And, is there a brass 'can' with what looks like a tire valve on top ? (an automatic float type air vent).

Waiting for pics ...

 

Sorry I haven't gotten back to updating this thread. Too many irons in the fire. I finally had to make time to work on the boiler the other day, as it was getting progressively worse lately. When I first typed this thread I plumb forgot about the temp/pressure gauge on the furnace, so I do have a pressure reading. the pressure was low. I turned the adjustment screw on the Pressure regulator (reducing valve) and it made no difference. So, I turned off a couple isolator valves and drained the boiler. I unhooked the pressure regulator and turned the water supply back on. No, water flow
I installed a new reducer valve, filled & bled the system, fired it up, and it's running like a champ.
In hind sight I think the pressure regulator (or reducing valve) has not been working properly for a long, long time. I haven't heard a peep out of the baseboards since. Just silent comfort.
Just thought I would let you all know the outcome. Thanks.

 

Thanks for the update Gary ... glad you had a good outcome!