Question about bleeding baseboard heat at boiler

Old 03-08-18, 04:55 PM
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Question about bleeding baseboard heat at boiler

Hi everyone, I have a hot water baseboard heating system. The system has two zones. In the past, I have had the HVAC guy bleed the system, but he is very expensive. I haven't been at home to see how he did it. I am willing to try it myself. I attached two pictures.

Do I connect a hose to the two red faucets and turn the spigot until water comes out of the hose? Also, is the water extremely hot?

He did tell me in the past that the upstairs zone bleed faucet is broken and has to be replaced. Is that easy for me to do?

In the past, I was told by my wife that he did not bleed anything at the baseboard units, only the boiler.

Thanks for your help!

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Last edited by PJmax; 03-08-18 at 06:49 PM. Reason: reoriented pictures
Old 03-08-18, 06:18 PM
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First off, the water is going to be what the temp gauge says it is so it could be very hot unless you shut the boiler down and let it cool first.

Next, I cannot tell by the pics but if it has a thread on it then it just screws in but you will have to drain the zone first before you unscrew it. When you do use 2 wrenches and apply even pressure the fitting it's screwed into so do don't break the solder joint.

I enlarged your pic and it looks like your faucet may be soldered in place which means you will have to know how to solder to replace it.

Now to bleed, you shut off your boiler so nothing is running. Shut off the blue handle shutoff valves and you bleed from the red handle valves but there is more to it than that.

You must feed in fresh water to the boiler to raise the pressure to about at least 25psi and keep under 30psi so the relief valve doesn't go off.

I cannot see how you are feeding your boiler to see if you have a fastfill or a bypass on your auto feeder to see if raising the pressure is possible for you.

Can you post pics of the boiler feed and the boiler with the correct orientation. That would be a big help.

Have you ever done any work on a boiler before. If you don't do this correctly you may lose your heat altogether. Why are you bleeding the system anyway.

Hope this helps a little.
Old 03-09-18, 02:53 AM
Join Date: Jan 2010
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Doesn't the term "bleeding" pertain to removing the AIR from a hydronic heating system . . . . and not the WATER ?

The OP's Post seems to indicate that his intention is to drain all the water from the system.
Old 03-09-18, 05:45 AM
Join Date: Jan 2008
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I have the same question as Vermont. Why do you want to bleed the system.

@mrdizle - Bleeding is not required for normal maintenance.

See the topic at the top

"DO NOT FLUSH your hydronic system every year!"
Old 03-09-18, 07:32 AM
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it looks like you have a automatic bleeder the gold thing screwed into fitting on top of boiler if not automatic then unscrew little cap and there is a needle valve like on a bike tube press in until just water comes out no air
Old 03-09-18, 01:44 PM
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Thanks for the replies. Earlier this winter, I suddenly had no heat in one zone. The tech came by and bled the zone and restored the heat. I was not there to observe what he did -- only my wife was at home and she had no idea.

My system makes A LOT of water rushing noises and grinding once in awhile. It is more noise than earlier in the season. That's why I think it is an air in the system issue.

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