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McDonnell Miller #150E

I am looking for any documents or bulletins on the McDonnell Miller 150E Electronic probe type low water cutoff and pump controller. Seems we have had a bunch of issues with failures of the control based upon dirty water, mineral deposits and or coated probes. (Although it certainly does not LOOK like there is enough build up to cause the failures) Can anyone point me in the direction of help or information or even experiences with these controls?

  We have been using #150S (snap acting) to avoid the issue but alot of existing boilers still have the 150E controls on them. Kind of pricey to just replace the heads with 150S models when customers are footing the bill.

  Thanks in advance for the help and feedback.

Jeff Krawic


  • Empire_2
    Empire_2 Member Posts: 2,343
    Hello JK?

    I believe McDonnell Miller as a pretty in depth web site, but I have not been there is at least a year.  I think it would be a good idea to check them out and see if they have any info on problems you are running into.  I have also filled out my CO info and was sent a wealth of info which I keep on the truck for such instances.

    Mike T.
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