Bleeding the Boiler

Bucho

Hello everyone,

Im new to the site and I was hoping I could get some assistance. I did some searching and wanted to double check if I was bleeding it right.

I recently purchased my home. The boiler is practically new and is about 2 years old according to the previous owners and inspector.

When I went ahead and turned on the heat I noticed the performance of the heat in the master bedroom was quite poor, and a loud banging noise was coming from the pipes. I knew right off the bat I had some sort of air in the lines.

I have baseboard hot water and it seems to be a closed loop. There are 2 zones, 1 for the basement 2nd is the 2nd floor. It has a spirovent above the hydronic expansion tank.

There are no bleeder valves on any of the baseboards. Trust me I checked. The system runs at 20 PSI hot.

I went ahead and tried to bleed the system by talking to a few buddies for advice.

I hooked up a hose and drained the water out of the system at the same time adding water back into the system and opening the zone on the thermostat on the boiler to Max Open. The Pressure dropped around 5 PSI and was holding steady. I normalized everything up and brought the pressure to about 15 PSI cold.

Now this has improved the heating in the master bedroom and the noise in that room , but now the banging noise has moved to another bedroom.

I did not experience any kicking of water so I am unsure if I bleed it long enough or the right way.

Enclosed are pictures of the boiler from top to bottom. Your advice would be GREATLY appreciated.




http://www.flickr.com/photos/rubennl...7609324325915/

beenthere

Did you shut the ball valve above the circ, and purge through the drain cock at that point.

If not, you didn't purge it right.

Bucho

No I did not shut any ball valve off. I am assuming the one in IMG_2830 on the bottom left hand corner, and then use that bib right above it to bleed the system?

pipefitter636

Looking at the pic's I don't really see an easy way to bleed the system of air,but beenthere is the expert. You could add a Hoffman #79 to the highest point of the loop this would bleed bleed the air on its own, and your prv would fill as needed.

beenthere

Yes.
That will force teh water through the loop.
May take 5 minutes, may take 15 minutes.
What air isn't purged by that method, will generally be removed by the spiro vent during normal operation afterwards.

Mainah

make sure that zone your trying to purge is "open" too- only open one at a time for beter results-

Bucho

Hey Guys,

I did the following at each zone and the problem still exists at the 2nd floor master bedroom.

Shut the Ball Valve above the circ.
Connected the hose and purged one zone at a time for about 10 minutes each. I could tell it ran though in about 5 minutes since the water temp was cold.

I did it last night and also this morning and noticed that this morning the Spirovent was spitting up some air and a few droplets of water.

The problem seems to get progressively worse though out the night just as the heat gets turned on.

At first i thought it might have been rubbing and removed the front covers of the baseboard, and was able to pinpoint it to about a 90 degree turn of the pipe that has another foot to go then back into the floor, but I was in a rush this morning and I am going to double check tonight.