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How often should boiler water be replaced on a 5 yr old unit?

How often should the water be replaced on a 5 yr old boiler? Should I flush the condenate pipes annually and how? Should I drain about the rusty water from the site glass and boiler regularly?


  • gary_6gary_6 Posts: 60Member

    You should be changing the water in your boiler two times per year.

    On the same day that I do this I also change the air in my car tires. You wouldn't believe how much smoother the car drives with fresh air in the tires plus you'll get slightly better gas milage.
  • John_173John_173 Posts: 63Member
    Steam or hot water boiler?

    (Disclaimer - I'm just a semi-educated homeowner.)

    If this is a steam boiler, you need not ever change the water. This assumes the boiler has been properly skimmed, etc. You're trying to introduce as little freash water as possible - to avoid the corrosive quality of the oxygenated water. Of course, over time you will need to add make-up water and of course you need to blow down the LWCO routinely and top the boiler up after. That, at least is my understanding.

    For hot water, the same corrosion issues would seem to come into play, but a system with antifreeze would change the approach, and (for all I know) so might some other circumstance.

    Just my understanding....

    (a later edit to my lunchtime post:)

    If the boiler water is filthy, foamy & bouncing in the glass, I believe it does need treatment/changing/skimming, etc.

    As far as air, I'm fairly full of hot air, but I don't believe I'm the sole source around here.
  • Roland_12Roland_12 Posts: 19Member

    OK on changing that tire air Mike. I do the same thing but use only the factory recommended air. It costs a bit more but you can really feel the difference.
  • SpeyFitterSpeyFitter Posts: 421Member
    OEM air...

    ... works even better. However, especially for vintage and antique car collectors, finding OEM air (if possible, from the year the vehicle was manufactured) is becoming ever more difficult.

    Shouldn't a cleaning chemical be added to the boiler before draining and replacing the water?

    Is there any way to flush the (1-pipe) runs and risers?

    Class 'A' Gas Fitter - Certified Hydronic Systems Designer - Journeyman Plumber
  • Roland_12Roland_12 Posts: 19Member

    Just try to find OEM air for one of these....
  • you guys are terrible advisers

    use nitrogen in the tires. you won't believe what it does for the handling due to the moisture displacement
This discussion has been closed.


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