Posted by Harold Kestenholz - Hydronic Network on February 05, 2000 at 22:55:58:
In Reply to: draining and refilling HB Smith boiler posted by Chris S on February 05, 2000 at 18:46:39:
Blowing down the system would be flushing air through a loop to blow air out of the line and move dirt out of the system. The vents at the radiators are for getting rid of small amounts of air. Once dirt and air are out of the system, the water inside is like gold. A water system is corroded by oxygen added to the system by adding fresh water, so you want to do that as rarely as possible. Chemicals in residential boilers are not recommended by manufacturers.
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