Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

Steam Pipes Chemical Cleaning

I’m having a new company service my 3 steam boilers in a 3 story 3 family house. They are recommending a chemical cleaning that they leave in the system for 3 weeks and come back to drain the system.

 The reason being is that the water is dirty and they said steam boilers like  clean water to make steam. I would like some expert opinions on if this will harm my system and what is an alternative solution to getting the water clean. Some of my return lines are copper. I’m not sure if that matters or not.


  • KC_Jones
    KC_Jones Member Posts: 5,261
    First of all anything they put in the boiler basically stays in the boiler, they aren’t cleaning pipes, if they say it will clean the pipes they don’t know what they are talking about.

    If the boiler has crud in it that is causing issues with heat transfer in the bottom of the boiler, then I can see value in flushing things out.  Depending on how bad it is could maybe require some kind of chemical treatment.  Though I’m a bigger fan of using a wand to clean things out if it comes to that.  I doubt many companies are even aware of this method though, and the piping needs to be such that it can be done.

    Now my question, what are they recommending long term to prevent this in the future?  Some of us strongly believe in water treatment through the use of off the shelf boiler treatment products.  Keeping the PH elevated can slow or even stop the corrosion causing the buildup of crud.
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • AdmiralYoda
    AdmiralYoda Member Posts: 496
    I use Rectorseal 8-way to keep my boiler pH in check. My manual says my pH should be between 7.5-11 and I add just enough to keep it around 9.5-10. It will clean any gunk that may have built up in the boiler but will also stop future corrosion.

    If they want to add chemicals to fix something or increase performance some how... it doesn't work that way. If they want to clean out the crud....okay. But a couple of drain and fills can go a long way.
  • JohnNY
    JohnNY Member Posts: 3,006
    This is not frequently observed, and I'm not sure if it's national, but Code says domestic water supply systems must be protected by a Reduced Pressure Zone backflow prevention assembly where connected to any system containing chemicals.
    Contact John "JohnNY" Cataneo, NYC Master Plumber, Lic 1784
    Plumbing in NYC or in NJ.
    Take his class.