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mcdonnell miller #67 LWC

mcdonnell miller #67 LWCHave a 120 v #67 LWC hook up to a 120V mcdonnell miller unimatch water feeder, LWC only works somtimes when i test it, i belive switch is getting caught up do i need to change entire unit? is it worth just trying to fix switch? Any suggestions or fixes the unit is not cheap.


eddie <a href="http://www.heatinghelp.com/forum-reply/1186523/mcdonnell-miller-67-LWC">Reply</a> <a href="http://www.heatinghelp.com/forum-edit-post/1186523/mcdonnell-miller-67-LWC">Edit</a>


  • BobbyG
    BobbyG Member Posts: 79
    repair or replace


    page 12 says it all for me..."SCHEDULE:

    • Blow down weekly (at least once) when the

    boiler is in operation.

    • Disassemble and inspect annually. Replace

    the low water cut-off if it is worn, corroded,

    or if components no longer operate properly.

    • Inspect the float chamber and equalizing

    piping annually. Remove all sediment

    and debris.

    • Replace every 10 years. More frequent replacement

    may be required when severe conditions

    exist such as rapid switch cycling, surging water

    levels, and use of water treatment chemicals.

    It is too critical of a device to not be sure if it will work.

    If it was me, if I were thinking about repairing the switch, I would take it all apart and make sure there isn't any debris or buildup anywhere.
  • Tim McElwain
    Tim McElwain Member Posts: 4,588
    Clean the low water cut-off

    and replace the switch, you should be all set after that. Just make sure the Sylphon Base Assembly (Float) does not have water in it if so replace it. Make sure to instruct the customer how to blow down and remove the spring loaded # 14 blow off with the new flush version.
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