How do I remove air from my system

Terence Quirke

Yes, I have baseboard heat.

Terence

Terence Quirke

Air in the heating pipes

I am a homeowner, not a plumber.

I have a hotwater heating system with five zones. In at least two of these zones (and I assume for the whole system) there is a gurgling noise when the thermostat calls for more heat. I presume the noise is due to air in the pipes.


So: how do I get rid of the air?

Thanks

Terence

Timco

may be low pressure. do you have radiators?

Timco

Try 'purging' the system. Put a hose on the drain cock on the return side of the zone to be purged, then bump the pressure up to about 25# or so. shut off the isolation valve below the drain you are hooked to and open the valve with the water still in the fill position. This combination of the system pressure releasing and the fill valve open should circulate the air through. Do this for each zone. You may also find bleeder 90's under the covers at one end of your BBs. single story house should run about 10-12# normally, but up to 15 is fine. Don't fill above 30# or you will need a raft of some sort.

T

jeff_51

just a note

that's 10-12 lbs when the system is cold, it will run around 20-22 lbs when hot

Timco

Good addition. Never do anything besides bleed to a hot boiler. Especially add water.

T

Terence Quirke

Tim White wrote:

Try 'purging' the system. Put a hose on the drain cock on the return side of the zone to be purged, then bump the pressure up to about 25# or so. shut off the isolation valve below the drain you are hooked to and open the valve with the water still in the fill position. This combination of the system pressure releasing and the fill valve open should circulate the air through. Do this for each zone. You may also find bleeder 90's under the covers at one end of your BBs. single story house should run about 10-12# normally, but up to 15 is fine. Don't fill above 30# or you will need a raft of some sort.


OK, I follow everything up to the sentence starting "You may also find bleeder 90's etc."

Can you explain a bit more, please?

Terence

Timco

Where the pipes come through the floor, the 90* elbo that ties into the BB heater may have a bleeding valve on it...on one side or the other. If not, you will have to use the purge method, which is best to perform first anyway, then bleed if you have any bleeder valves. The sides of the BB heater should just flip up to see the connections.

T

Terence Quirke

There are no bleed valves on the baseboard heaters.

However, on the horizontal return main there is a place near the end before the pump which is wider. Below this is the Extrol tank and above is a silver cylindar about 2.5 inches tall and 1 inch diameter. On top of this is a green thumb screw that seems to be screwed down all the way.

Can this be an air bleeding valve and only needs to be unscrewed a bit to allow the air out?

Terence

Timco

Yes, this is a bleeding valve, and I assume was meant for the air to rise up into the enlarged area and to be bled out from there. A bleeding valve is usually at the highest point of the systems, like mine on top of the radiators, because the air rises. Maybe try bumping up the pressure, and running the circulator and keep the valve open a bit, and see if air rises to the top of this fitting as it passes by.

T

Timco

You can replace that valve with a taco or honeywell air-eliminator, which will automatically allow the collected air to escape. You should only have air in the system after fresh water is introduced, and this devise is cheap and should just screw right into where the bleeder valve is. A plumbing supply store should have it.

T

Terence Quirke

OK, Tim, I'll try that.

Thank you very much for your help and your patience.

Terence

Terence Quirke

OK, that seems to have done the trick. No more gurgling noise, anyway.

Some local plumber may go hungry because I didn't have to call him out. But I'm sure there are lots of other jobs where he's required, tho.

Thanks, again.

Terence