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L W C O Help

Fefe Member Posts: 1
We bought a house about 3 months now and the heat has been working just fine. However we recently found out that the LWCO have been calling for water from the automatic water feed more than usual and when it does call for water it does not signal the boiler to turn back on instead it keeps calling for water. The probe was inspected but not much dirt was found on was cleaned never the less but the problem persists. Can some one please tell me what could be the problem? Does this mean the LWCO is broken. The LWCO is Mcdonnel and Miller brand.


  • ed wallace
    ed wallace Member Posts: 1,613
    lwco help

    the auto water feed does not tell boiler to turn back on that the low water cut off does if its a float type the float bowl is plugged and needs cleaning or replacing if a probe type then the probe needs cleaning
  • LWCO problems

    is this the model with a safety reset button? if so then you need to find out where the water is going, and hides out. observe the firing cycle and see what may be happening to the water.

    possible causes would be: too high a steam pressure, forcing the water to back up into the dry return, thus temporarily depriving the boiler of water. get a good low-pressure gauge [ 0-2 psi] and have it put on next to the original 0-30 psi gauge, which must stay. pressure should be less than 1.5 psi for the main vents to operate properly, and if economy is desired, under 12 ounces, which requires a vaporstat.--nbc
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