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Draining Old Boiler Question

I have an old American Standard G-40 Gas Boiler. It has a McDonnell Boiler Control (Model No 47-2). From my understanding  I need to open the blow off valve and flush out the chamber 1x/wk during heating season. There is another valve (with a garden hose attached to it located at the bottom of the boiler). Some have told me I need to drain this every month. Some have said just drain as much to get rid of the dark water/sludge and others have told me not to touch it (it can be harmful to introduce fresh water to the boiler (increase oxidization?).  What is the correct procedure? Thanks for any help.

Comments

  • Long Beach Ed
    Long Beach Ed Member Posts: 1,321
    Draining

    About a bucket of water should be drained from the low water cut-off's blow down valve every week or every two weeks during the heating season.  If this is done while the burner is running, the control can also be tested this way. 



    Otherwise, the less fresh water admitted into the boiler, the better. 



    You may wish to drain all the water from the system once each year before the heating season and then boil the water for a few minutes to drive out the harmful oxygen. 
  • Drain....

    The bottom of the boiler should be flushed occasionally to keep it from getting to much debris build up.  Open it long enough to get the heavy crud out and murky water and thats it.  How often you'll need to do this depends on the condition of the system, so every boiler varies.  I usually tell clients to open it ounce a month and see how bad it is.  If it is staying clean, longer intervals are OK.  If you add water treatment, it will keep the boiler and system alot cleaner by reducing or eliminating corrosion.   See Rhomar water conditioning.

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  • sweetlou
    sweetlou Member Posts: 22
    Thanks

    Thanks for the help.
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