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Weil Mclain Ultra 750

richper Member Posts: 1
We have a new account with two ultra 750 boilers. I did a water ph test kit on the system and the test failed. My question is how much of the sentenial 100 treatment will it take to bring this water to pass the test. This is a 3 story senior living building with a primary secondary loop. All baseboard throughout.
Also, when doing the yearly maint. as per the boiler manual, it was a real bugger to get the blower assembly off the studs to get to the burner. The book doesn't say anything about unbolting the gas train. It seems to me that's probably the best way to do it.
Any advise would be greatly appreciated.


  • Tom_133
    Tom_133 Member Posts: 773
    I know the sentinel is expensive but as fas as I know you can't add too much, what I mean is you can only hurt boiler if don't put enough in too much won't hurt so a couple trips is to be expected unless you do the math to figure out how much water is in that system. Put 4-5 tubes in go back in a week after a week of running and test it, don't bother testing that day it's a waste of a test kit. Also any cleanings I have done on any Ultras (never a 750 though) have come with a gasket in the service kit to remove gas valve from blower.
    Montpelier Vt
  • eachone
    eachone Member Posts: 1
    we are installing two new ultra 750 boilers (retrofit) and cannot because of the equipment and other existing piping in the boiler room get the manifolds in the main heat loop for the supply and return as close as the instructions specify. (A maximum of 8 diameters apart) What would be the main problem if they were 10-1/2 diameters or, 42inches instead of 32inches?
  • Paul S_3
    Paul S_3 Member Posts: 1,257
    edited August 2016

    are you referring to the closely spaced tees in the manual...if you are you will create flow in other parts of the system .....the idea here is to keep the flow through the boiler only and seperate from the system...the boiler has a minimum flow requirement through the heat exchanger....they call it hydraulic seperation.....why cant the piping be changed? do you have a pic of the piping?or can draw on....i would pipe this boiler to the exact specs in the manual. Are you referring to the slimfit 750 in the pic below? ive installed a few of these...
    ASM Mechanical Company
    Located in Staten Island NY
    Servicing all 5 boroughs of NYC.
    [email protected]
  • Zman
    Zman Member Posts: 6,993
    edited August 2016
    A good hydraulic separator will perform better than closely spaced tees. In some cases they are easier to install.

    BTW @eachone It is always better to start a new post when you have a new subject. I gets confusing when part of the post is about water chemistry and another about separation.
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein