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Boiler cleaners and old radiator systems

DJS Member Posts: 4
Hi all. Big fan of this site. Just a little about me first. I'm a master plumber and the licensed Hvac holder for my company. Been doing this for about 20 years. I work for a company that installs furnaces and boilers for low income home owners through money from local utilities weatherization program.
Here is my question. I was always taught from early on, that introducing chemicals into a boiler system is a last option. But just about all the boiler manufacturers of condensing boilers are requiring that you must do a boiler system cleaning before changing the boiler. My fear is that this can and will cause leaks throughout these old radiator systems that I will end up spending huge amounts of time fixing or replacing that cant be budgeted for. Am I thinking too much into this?
Also, adding an inhibitor after I install a new boiler. Odds are that even though we are installing condensing boiler, that the clients will not probably do yearly maintenance. I'm worried that if the inhibitor is not checked regularly, it may become the cause of future problems.
I do understand the irony that we're putting in high efficiency systems for people that are not likely to do the proper maintenance. But I have certain AFUE standards that I must meet.


  • kcopp
    kcopp Member Posts: 4,441
    Things are changing.
    A cast iron block can handle stuff that stainless or aluminum cant.
    Circulators are changing too. The new ECM versions wont last long if you have dirty iron filled water.
    Cleaning the system should not cause leaks unless the system is compromised to start. Cleaning can be done w/ a proper chemical (Fernox, Rgomar, sentinel, etc) or a good power flush.
    Once that happens you could fill w/ De-ionized water and that may very well be all you need.
    Or you can add a good inhibitor to decent water. If you have bad water you are starting w/ a strike against you.... just look at places where some water heaters will last decades and other places where 6 years and you are done is common.
    I do believe inhibitors can wear out but unlike glycol they don't wear out and turn corrosive to the system.
    If you install high efficiency you will need to service it more often... no way around that. if they will not do that than maybe/ probably that's the wrong unit to install.
  • ADEY_NorthAmerica
    It is true that older furnaces and boilers were able to work regardless of the debris floating around within the heating system. This is because the flow channels are so big that it really didn’t matter and the system was unlikely to block. With a modern condensing boiler, the flow channels are so small within the heat exchanger, and in the ECM pump that water treatment really needs to be taken seriously. Over here in the UK, more than 85% of callouts to boilers within the first year of warranty are due to poor water treatment.

    In Europe we have a great deal of experience of treating and maintaining condensing boilers because we have had them a lot longer, so it is something that the US can learn from the European model. Over here we clean a system using a neutral cleaner in most cases, and then inhibit with a well-balanced, pH buffered inhibitor. In the UK, we have a standard for these, CIAS (Corrosion Inhibitor Approval Standard) operated independently from the industry. We have also developed some very innovative solutions for removing magnetite, based on high-performance magnetics and we also have filters using the same technology that remain in the system to give you that ongoing protection year after year. Over 4 million of our filters are installed on the UK market alone.

    Just to reassure you, a well-balanced inhibitor will not be detrimental to heating system even if it is not checked or maintained on an annual basis. Obviously that would the best maintenance regime, but most of these products are formulated to give ongoing protection to the heating system for at least 5 years, after which their efficacy may be reduced, but they will not become detrimental which, you are absolutely right, may be the case with a glycol.

    Kcopp’s response to your question is a very good one, the only exception I would make is that deionised water on its own, is not a good enough solution. In theory, and in the laboratory, in systems that are completely closed to atmosphere it may work, but in the real world it does not. Even if treating a system with deionised water, we would always recommend the addition of an inhibitor.

    Adey is the biggest water treatment manufacturers for residential systems in the UK, and now all of our solutions are available in the USA. Our website www.adeyusa.com will point you in the right direction.