Click here to Find a Contractor in your area.
Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit

MM #42 vs a #67

Just curious,

Is there any reason I couldn't use a #67 LWCO to replace a #42?  The 67 has contacts to control feeding a water feeder too.  Just curious.  There is a boiler feed pump on the system for making up water.



  • Steamhead
    Steamhead Member Posts: 14,850
    The #67 should not be used for a boiler-feed pump

    Pumped-return requires the switches to activate every time the boiler needs water. The #67's switches aren't up to that job. They're fine for the occasional water feed on a gravity-return system, but that's it.
    All Steamed Up, Inc.
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
This discussion has been closed.