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67 LWCO wiring torubles (STEAM)

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Snips
Snips Member Posts: 4
in Strictly Steam
Hey everyone I have received help from some of you before which solved my past issue so I am hoping this time around will be the same. My steam boiler setup is as follows: Peerless G-561-SP-D, Mcdonnell & Miller 67 LWCO, WFE-24 Feeder, Honeywell Pressuretrol. I am in the process of replacing the LWCO and WFE-24 feeder. I have been following wire Diagram 4 on the WFE-24 install manual. While connecting the wiring I was checking the voltages with a Fluke T5-600. With HOT wire connected to terminal 2, terminal 1 puts out voltage (26v). According to the diagram terminal 1 should be neutral. Is this normal operation? Is it normal to connect a neutral wire to terminal 1 knowing terminal 1 is putting out voltage?

I am also confused with the wiring of the pressuretrol. The original wiring of the pressuretrol seems to have been connected to the LWCO terminal 1 and 2. Is this normal wiring? I assume the pressuretrol was receiving power from terminal 2? Because of this past configuration I am confused as to how to properly wire the pressuretrol. If you need more information I can provide it. Thank you for reading this.









Comments

  • Abracadabra
    Abracadabra Member Posts: 1,948
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    Terminal 1 is not neutral. I don't see how you came to that conclusion. According to the wiring diagram, terminal 1 is the hot to the burner.
  • Fred
    Fred Member Posts: 8,542
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    The safety devices are wired in series. One wire from your Pressuretrol goes to Terminal #2 on the MM67. One wire from the burner goes to Terminal #1 of the MM67. Wire the auto feed to the terminals on the MM67 per the instructions from the Auto feeder mfg.
  • Chris_L
    Chris_L Member Posts: 336
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    Fred said:

    The safety devices are wired in series. One wire from your Pressuretrol goes to Terminal #2 on the MM67. One wire from the burner goes to Terminal #1 of the MM67. Wire the auto feed to the terminals on the MM67 per the instructions from the Auto feeder mfg.

    Are you sure about this? It make sense to me to wire it as shown (with the Pressuretrol between Terminal #1 and the burner)--if Terminals 2 and 3 are supposed to always be hot.

    Terminals 1 and 2 are the switch to shut off the boiler on low water. Once the water drops too low, that switch is open. If you make the connections as Fred suggests, and wire the Auto feeder as shown, Terminals 2 and 3 won't have power once the switch between 1 and 2 opens.

    I would think you would always want Terminal 2 (and 3) powered so that the when the Auto feeder switch in the LWCO (between Terminals 3 and 4) makes contact on low water it sends power to the Auto feeder.

    Am I missing something?
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,519
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    Wire as shown in the wiring diagram. Put all other or additional safety switches between terminal #1 and the burner.

    This way the feeder can always operate
  • lchmb
    lchmb Member Posts: 2,997
    edited January 2017
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    ..
  • Fred
    Fred Member Posts: 8,542
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    @ChrisL , I guess I should not have said "wire the Auto feeder as per the instructions from the manufacturer" without having looked at those instructions. I have the MM67 installed on my boiler and terminal #1 is to the burner, Terminal #2 is to the Pressuretrol. I removed my water feeder two or three years ago.
  • Snips
    Snips Member Posts: 4
    edited January 2017
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    Hey everyone thank you very much for your input, direction and clarification. I have wired everything as shown in the diagram. LWCO and feeder work together as they should. I am now having another issue. The burner is not igniting. The pilot lights and stays lit however when adjusting the thermostat up the burner doesn't ignite. I have twisted the ends of the wires together on the thermostat and turned the power on.. And.. No sounds nothing. The thermocouple is red hot. I am thinking a wiring issue. Your help and advice is much appreciated. Thanks again.

  • Abracadabra
    Abracadabra Member Posts: 1,948
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    verify if there's power to the gas valve. work backwards from there to find what's interrupting it.

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