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How does water quality effect steam boilers and piping?

Dairon421 Member Posts: 80
This house I'm going to have alot of pinhole leaks. I was thinking  about testing the ph level but wanted to chat with you guys first  before doing so.


  • Jamie Hall
    Jamie Hall Member Posts: 22,941
    The main effect of boiler water quality is on steaming, and you really want the pH somewhere between 7 and 9. So far as corrosion and leaks is concerned, the parameter you are looking for is total dissolved solids, and you want that low -- but not too low.

    If the pinhole leaks are in the wet return piping, it is just as likely that the corrosion is coming from the outside as the inside, particularly if there is mortar or concrete dust around.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • clammy
    clammy Member Posts: 3,094
    Pin holes in steam mains are usually related to a few other issue not ph. Every system I have ran into w pin holes in the mains suffered from the following issues if not all which contributes to pin holes
    1 poor near boiler piping creating wet steam and tossing water into the mains . NG
    2 improperly or not pitch on piping including sags and bellies which hold condensate .NG
    3 Inadequate Main venting leaving a mixture of air in the mains which over time forms a carbonic acid andalao will make your condensate become acidic this will also help produce pin holes
    4 no insulation ,without your steam main being properly insulated Steam will fold into condensate ,producing more condensate then a insulated pipe . Excessive condensate in steam mains will start to groove the bottom of the piping and usually rot right threw the thinnest part of your piping usually where the pipe is threaded into a fitting.
    5 excessive make up water due to wet return leaking , bad vents passing steam ,bad main vents passing steam ,leaking radiator valves and packing nuts.
    These are my usually suspects from over 30 years of spinning pipes , believe what you want but the truth is always the most obvious and usually not the cheapest solution and something that ones with no experience couldn’t t even phantom or understand .
    6 clogged and slow wet returns , they make water back up into the supply mains creat a lot of water hammer and also will give a helping hand in pin holing and rotting your mains . This is something else that I have first hand seen and repaired .
    You can chk your ph but I doubt this is why your steam mains are pin holing . If you had acidic portable water you surely would have had pin holes in your copper water lines by now .
    Has anyone ever cleaned your boiler out ,by removing the plugs and wanding the boiler sections out to remove mud and rust build up . Not many due they just say yeah we cleaned and serviced the boiler but never really wand the boiler out ,flushing does just about nothing except appease the HO .
    There will be those who replace your rotted sections w copper you should show them the door and find some one who will replace your piping w steel pipe and also be sure that they will flush out your wet return and if there’s no provisions ( boiler drains ) then allow them to install them , be sure the boiler is wanded and clean ,site glass , low water cut off probe and return inlet .
    I get new customers all the time that swear that there last service company hadn’t cleaned the boiler . I clean it they watch and say the other guys never did that I say yeah i know then they see about 15 to 20 minutes of pure mud and crap get wanded out of the boiler there’s amazed . What amazes them next is how different there boiler operates once it clean what took 20 to 45 minutes for the end of the main street to get Hot’s now is done in less then 15 minutes . Not all service provides do the right thing espically when your talking steam . As a retired sensi has stated it’s a lost art this I am very sure of . I hope you find some one who will tell you the truth instead of yanking you’re pocket book
    Peace and good luck clammy
    R.A. Calmbacher L.L.C. HVAC
    NJ Master HVAC Lic.
    Mahwah, NJ
    Specializing in steam and hydronic heating