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ncdebbi

Bleeding air from Hot Water Baseboard System

ncdebbi
17 years ago

We have a 3 zone system that has gotten very noisy this season from air getting (?) in the system. First we're not sure where the air is coming from. Second, we can't seem to get the air out when we bleed from the baseboard units. We've had trouble with one zone for a few seasons now and the second one just started this season. The third zone is quiet...at least for now :)

After reading several posts here, I realize there is a way to bleed the system with a hose.

We tried to do this based on a compilation of different posts, but we must be doing something wrong...still gurgling! I had the hose connected to the spigot which is located above a shut-off valve, which is located above the thermostat (one set-up like this for each zone), the hose I ran upstairs, above the highest baseboard, and into a large bucket (which we emptied several times, rotating buckets). I made sure the zone was on and water was moving through the zone. We did one zone for 45 minutes!

Can someone detail this process for us? Also, how long does it usually take to completely bleed a zone?...I mean, how do you know when you've completely purged each zone? The water gushing sounds are so frustrating...and I read that it's not good for the boiler, so we definitely want to remedy the problem.

Thanks for posting!!!

Comments (10)

  • blacknumber1
    17 years ago

    You need to bleed air from the units on the top floor of your home, and you also need to make sure your make-up water is turned on when you do, the air cannot get out if there is no water to replace it. Do you get water out of all your baseboards in the problem zones?

  • baymee
    17 years ago

    As I posted elsewhere, I was never able to stop the running water sounds until I bled the air out of the top of my boiler. Welding processes and fittings on some boilers will allow about a cup or more of air at the top of your boiler to be captured. That's all it takes. I bled mine by slowly cracking the pressure relief valve.

  • tommy23
    17 years ago

    I had the same problem ,I remember the serviceman came and opened the Taco water pressure reducer to allow more water into the loop of the zone as he open the zone v/v manually while the hose was connected and run into a sink. The whole zone was runnig the fresh water in and the old water out ,I watched the the hose jump(belch) as the air was being forced out . when the hose was not jumping anymore he shut the Taco water pressure reducer and closed the water drainage v/v . He did not open any bleeders on the baseboard radiators . I hope I'm right ,perhaps someone can clear it up ,it was a couple of years ago .

  • baymee
    17 years ago

    You may find few baseboard bleeders. They aren't usually necessary and price conscious people won't pay extra for them or vice versa, a low bidder won't list them.

  • ncdebbi
    Original Author
    17 years ago

    Thanks for the posts...baymee, I don't think I have a bleeder at the top of my boiler. The only thing on top is a gauge and the chimney pipe. I do see the Taco cartridge circulator and the pressure reducing valve that I've read about...this is shaped like a bell with a handle that flips over the top...is this how to bipass the pressure reducing valve and allow more water to flow? Is there something I need to do before doing this, so as not to cause harm to anything by allowing too much pressure?

    One more thing, this may sound like a silly question, but what does zone v/v mean? Is this the zone valve that's part of the thermostat which opens the zone? I want to make sure I'm doing everything right :)

    Thanks for the help!

  • baymee
    17 years ago

    You should be ready to purge when you open the water valve or your city pressure could cause the pressure relief valve to blow off. Otherwise, leave the lever in the low pressure position. The zone valve is the entire assembly, consisting of the heater and the actual valve. The heater can be removed easily for replacement.

  • rdsox_comcast_net
    15 years ago

    My understanding of purging air out of the system from the boiler, is that you are actually only bleeding the 1 1/2" feeder pipe supplying water to your baseboard, not the actual baseboard radiator. So you will actually need to bleed your radiators, after bleeding the air out of the 1 1/2 pipe

  • triq
    15 years ago

    Same exact thing is happening with me in our second floor zone.
    Could someone do a step by step, hand holding, description of the bleeding process with out the use of abbreviations. I guess I am not hip to all the heating /plumbing lingo.

  • bradley1982
    12 years ago

    Hi my registers are not working, or producing heat, my landlord said I need to bleed the registers until all the air is out and water comes out. He said it is done with a bleeder screw, but I have searched my registers and cant find any bleeder screws. Does anyone know where I can find them or how this is done. Thanks

  • Capt.Kraz
    9 years ago

    Hi, just read through the posts here. We have major gurgling etc., in our system. I think (I hope) I understand what needs to be done, but I don't have any valves or such on any of my baseboard units. Nor can I find any spigots or release valves in the basement where the zone controls are... Any suggestions?