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remove the air from your boiler / heater
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I had recently replaced my expansion tank but have air in my system. Right before my boiler return there is a cut off knob. The blue one above it has a spigot. then the zones above with their own cut offs. I’m looking to bleed the air out of both zones. I guess these are done together since there is 1 spigot. Other directions I found online show opening the zone valve while doing this. just looking for clarification.
mnewbegin
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Yes the blue valve. Zone valves should be on the return side. So do one at a time with the one furthest away first. Like the 2 nd floor. Keep in mind when you open that valve the system will start to drain. So it will be important that you allow fresh water to enter.
This is usually done by opening the regulator up a little at a time, kinda like here and there while bleeding it out.
Also make sure that zone valve is open while bleeding. Once the system is up and running pay attention to the pressure. You’ll want 15-19 pounds