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water pH

Bill_112 Member Posts: 14
I have a Weil McLain ultra 115 series 3 and I can not get the pH of the water down. It is 9.25 after flushing it with city water 3 times over the past year- the city water is at pH of 7 to 7.5 I can flush the two loops with out letting in air due to the proper placement of 1/4 turn valves. Will the Rhomar additive for aluminum boilers help adjust the pH???


  • Jean-David Beyer
    Jean-David Beyer Member Posts: 2,666
    I would love to understand this.

    I have a Weil McLain ultra 80 series 3 and I have a similar problem, though not as severe. My city water is between pH 7.2 and pH 7.6 according to the water company. I tested it with a pH meter and this seems to be the case, though on the low end. With pH paper, it is about pH 6, but I am inclined to go with the meter.

    When first installed in May of 2009, I checked the pH of the loop to the indirect hot water heater and all was normal. But no heating of the house was taking place because it was pretty warm inside and out. Now that it has been heating for a while, the pH is up around 8.2 (and I am allowed to go to pH 8.5).

    I am at a loss to explain why the pH has gone up. I have turned off the make up water, keeping an eye on the pressure gauge, and it is not taking on water. The slab is copper tubing. Upstairs is copper as well with Slant/Fin baseboard.

    So why is the pH going up? Is this common?

    Weil-McLain a little while ago recommended using an additive in all Ultra 3 boilers just in case. It seems to be Sentinel X-100.
  • Tim McElwain
    Tim McElwain Member Posts: 4,574
    What is the number of

    Rhomar Additive you are planning on using? You may be getting a breakdown of the water due to aluminum oxide. I really suggest you get in touch with Weil-McLain and get their input on this.
  • Bill_112
    Bill_112 Member Posts: 14

    I just spoke to the rep. at Rhomar and he suggested the Pro-tek 922. It is safe for aluminum. He also suggested correcting the pH with distilled white vinegar before adding the Pro-tek 922. 1 gal. of the product will treat 50 gal. of water.

    I am doing this homework before calling for help- I have a great service tec. but the homework I do always seems to pay off in the long run. Any other thought are always appreciated.
  • Tim McElwain
    Tim McElwain Member Posts: 4,574
    I put through

    these questions to a Weil-McLain rep and hope to hear back from him soon. I will keep you posted.
  • Tim McElwain
    Tim McElwain Member Posts: 4,574
    Bob Mercer

    from Weil-Mclain suggests:

    There is a product now available through Weil McLain wholesalers called Sentinel 100 which should do the job. Sounds like the water in this job is not getting flushed in every zone. A system with 7.5 pH must be mixed with something to get to 9.0.

    Sentinel should get this pH in line

    Bob Mercer

    Sales -  New England

    100 Medway Rd

    Milford, MA 01757

    Business Phone  508-478-6800

  • Bill_112
    Bill_112 Member Posts: 14

    The information is greatly appreciated.
  • Weil Mclain Bulletin, MB-0913

    Here's an old link for the Weil Mclain Bulletin, MB-0913 referencing Sentinel X100 additive.

  • Bill_112
    Bill_112 Member Posts: 14
    Sentinel 100

    The procedure for installing this product is great. Put the tube in a caulking gun, take the pressure off the system, remove a bleed valve on a radiator in the highest part of the house. After screwing on the injector you pump the product into the radiator, open the isolation valve, re-presurise the system, bleed the radiator then start the heater. Never get air into the system this way. Great idea and no draining of the system!

    Thanks for all the help
  • Bill_112
    Bill_112 Member Posts: 14
    pH corrected

    The Sentinel X100 did the trick- pH down to 8.3. Great product and easy to add to the system. Full marks!!!
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