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correct level

Turbo Member Posts: 8
Hello, this is my first post here.  I need some help with an old Weil-McLain model H5.  For many years I have been manually filling it to halfway on the glass.  I want to buy the 101A-24V feed valve which is the correct one for the boiler.  I noticed a strange thing when I was looking at the boiler.  I was looking at the low water cut off Mcdonnell-miller 67 which has the feed contact.  The float switch is very low compared to the sight glass. The float would only let me have about one inch of water showing in the sight glass.  The sight glass is 6 inches long?  Is this correct?  What is the proper level to keep the water?  I also noticed the fill contact and the low water contact are very close to each other in regards to the water level?  When my boiler makes steam the water level bounces up and down many inches.  Wouldn't this trigger the low level and shut down the boiler. One more thing I should mention is this boiler also make domestic hot water.  Thank you for your help. Joe


  • Al Letellier_21
    Al Letellier_21 Member Posts: 402
    water level

    You gave out a key hint as to the primary problem with your system, and a mechanical or float operated feeder is not the solution.

    Water bouncing "several inches" in the glass is an indicator of a dirty water side in the boiler or some other piping issues. You need to clean and skim that boiler and have the piping checked for proper sizing and installation methods. Normally you are correct in that the LWCO keeps the water low in the glass. If you have a coil in the boiler, you should keep the level higher to keep the coil submerged and working to peak efficiency. If the system is operating correctly, piped correctly, venting properly and maintained regularly, you should be able to manually adjust the water level and it should stay there all season !!!

    I would recommend you get a steam pro in there to help you. I would use an electronic feeder that can delay filling to allow for any issues with piping or partially plugged returns. Hydrolevel makes a very good one (VXT) and we use it all the time to replace overfeeding mechanical/float type LWCOs.

    Good luck. 
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