How to remove air from baseboard/hot water heat system
#1
Member
Thread Starter
Join Date: Oct 2013
Location: United States
Posts: 87
Received 0 Votes
on
0 Posts
How to remove air from baseboard/hot water heat system
So what's the best way to take out air from this type of system. This is a three family house. Each floor has their own Thermostat. As you see in the pics, there are 6 ball valve on the left. Two for each floor. Also have three zone valves.









Last edited by NJT; 10-31-13 at 04:20 PM.
#5
I am the owner. I just want to know if anyone here can recommend a different trick than what I do.
So, why not tell us exactly what it is that you do and we'll tell you right or wrong... would help us not having to reinvent the wheel for you.
#6
Member
Thread Starter
Join Date: Oct 2013
Location: United States
Posts: 87
Received 0 Votes
on
0 Posts
I do floor by floor. The floor I am working on I would put the zone valve to open from Auto. So as you see each ball valve has it own standard/old style valve right below it. So for that floor I would attack one valve at a time. I would close the old valve attach the hose and open the ball valve. I force the water from the main inlet so it forces all the air out. I wait until water is smooth and not spitting. I than close the ball valve and open the standard valve below it to allow water to go through. Than I go for the second ball valve for the same floor and do same. After one floor is done I put the zone valve back to Auto. I repeat this procedure for rest of the system.
#7
That sounds about right... I'll take a look at the pictures in more detail later this evening.
The problem with purging air in this fashion is that every time you add fresh water to the system you are also adding the dissolved air into the system as well. That air comes out of the fresh water and forms new bubbles as soon as it is heated by the boiler. Then, you have to start all over again... a vicious circle, catch 22.
ALSO, perhaps worse that that is the MINERALS, the calcium and magnesium that come in with the water and precipitate out forming scaling where you don't want it...
It's always better to add as little NEW water as you can... and to find the reason why you need to continually bleed the air instead... if you can get to the the root cause for the reason the air is there in the first place you may not have to do this time after time...
The problem with purging air in this fashion is that every time you add fresh water to the system you are also adding the dissolved air into the system as well. That air comes out of the fresh water and forms new bubbles as soon as it is heated by the boiler. Then, you have to start all over again... a vicious circle, catch 22.
ALSO, perhaps worse that that is the MINERALS, the calcium and magnesium that come in with the water and precipitate out forming scaling where you don't want it...
It's always better to add as little NEW water as you can... and to find the reason why you need to continually bleed the air instead... if you can get to the the root cause for the reason the air is there in the first place you may not have to do this time after time...
#8
Member
Thread Starter
Join Date: Oct 2013
Location: United States
Posts: 87
Received 0 Votes
on
0 Posts
I mostly end up doing this at the beginning of the season when I turn on my heat. I wait about three days before I do the air removal procedure. Sometime i have to do it in the middle of the season.
#9
Looked over your pics a bit more now that the boss isn't wondering why I'm not doing what I'm supposed to be doing! 
It would seem that there is no 'air removal' devices built into your system. Typically there would be an 'air scoop' like this:

image courtesy pexsupply.com
and on top would be an 'automatic air valve' that would release trapped air to atmosphere. Looks like this:

image courtesy pexsupply.com
Newer fancy stuff like Spirovent exists which claim to do a better job:

image courtesy pexsupply.com
While these might not completely eliminate the need to occasionally bleed air, they would certainly lengthen the interval between need.
Are there no bleeders on the individual radiators in the units? Or would going into the units upset tenants too much? It would be much better if you could just let the air out and not introduce a full pant load of fresh water each year.

It would seem that there is no 'air removal' devices built into your system. Typically there would be an 'air scoop' like this:

image courtesy pexsupply.com
and on top would be an 'automatic air valve' that would release trapped air to atmosphere. Looks like this:

image courtesy pexsupply.com
Newer fancy stuff like Spirovent exists which claim to do a better job:

image courtesy pexsupply.com
While these might not completely eliminate the need to occasionally bleed air, they would certainly lengthen the interval between need.
Are there no bleeders on the individual radiators in the units? Or would going into the units upset tenants too much? It would be much better if you could just let the air out and not introduce a full pant load of fresh water each year.
#10
Member
Thread Starter
Join Date: Oct 2013
Location: United States
Posts: 87
Received 0 Votes
on
0 Posts
I think I have the automatic air valve. It's located right behind the black water pipe. It's not visible in the the pictures. I'll take a better picture. I guess I am not sure how to use that part or does it work on it's own?
#11
I guess I am not sure how to use that part or does it work on it's own?
That cap on top needs to remain LOOSE in order to allow the air to escape.
If the cap is tight, loosen it a couple turns. If it leaks water, it needs to be replaced. You should get only air out but those things have a tendency to get mineral buildup around the valve part and leak. Usually people just close the cap tight and forget about them. They can be operated manually too... open cap once in a while to let the air out.