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Constant foam and rust in water

Good Evening everyone! I'm new to steam as I bought my 1908 home back in August. We had to replace our boiler as the previous one got so loaded up with crap that it was trying to push steam out of the return. I have a new Burnham boiler and very much enjoy having radiant heat! However Im having an issue with constant foam and rust in the water. I have been skimming the boiler every few days. However, after five times skimming the boiler I go through the same cycle-it works great for a couple of days, then the sight glass fills with foam and the water level drops during operation. I dont have a serious leak since the water returns when the boiler is done running, but I want to know if I should be doing something else other than constantly skimming and refilling. I know that constantly introducing water to a boiler is not a great thing!


  • mattmia2
    mattmia2 Member Posts: 9,623
    Steam being pushed in to the return from the boiler is caused by incorrect pressure settings of malfunctioning pressure control or occasionally incorrect piping. It is much more common for steam from the mains to get in to the returns because of failed steam traps or piping that is no longer far enough below the water line because of a boiler replacement.

    Did someone put chemicals in the boiler wathe? Priming is not caused by oil but by high ph or detergent in the water. you may need to drain and refill be boiler and returns, not just skim.
  • JeremyB
    JeremyB Member Posts: 2
    Thanks, Ill check the ph. My boiler guy checked it but I didnt get an actual number. I have drained and refilled it a number of times already, but no chemicals have been added to the water. The return piping was redone when I got the boiler to be lower than the water line, the original header was also improper. The original boiler was set at 8psi!
  • neilc
    neilc Member Posts: 2,702
    and what pressure are you set to now ?
    Ptrol should be shutting off at < 2 PSI
    known to beat dead horses
    STEAM DOCTOR Member Posts: 1,965
    Are you sure that you are skimming properly? How old is your wet return