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Troubleshooting a 2-Ton Fire Tube Boiler

King_Cas
King_Cas Member Posts: 2
in Strictly Steam

We are troubleshooting an old 2-ton fire tube boiler equipped with a Satronic MM87 controller and an FZ 711S Satronic oil burner photocell. The boiler ignites and combusts properly but fails to continue running due to a burner lockout trip. Unfortunately, I don't have access to the manual.

Can anyone explain how the photocell works and how to test it? I tried using a light source, but the issue persists, leading me to suspect a malfunctioning photocell. How can I confirm if it's faulty?

Any guidance would be greatly appreciated.

Comments

  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 16,934

    Are you sure it is a photocell? If it is it should respond to a lightbulb. I would put a test meter on the control to check the photocell. The burner manual should tell you how to hook up your meter. Depending on the control you have you may need an adapter to plug your meter into the control test jack. If the control does not have a test jack you can wire your meter in series with the photocell.

    Again, the burner manual or the control data sheet should show you how to do this.

    If it really is a photocell, they can only be used on oil they do not respond to a gas flame. If the burner lights the control and photocell must prove the flame. You could have a bad control, photocell or wiring between the photocell and the control.

    King_Cas
  • King_Cas
    King_Cas Member Posts: 2

    Thank you for your response.

    We currently have two 15-ton water tube boilers, but our boss wants to revive an old 2-ton fire tube boiler, which is why I don't have any manual or documentation for this unit.

    From what I found, the FZ 711S is a photo-resistor type flame sensor, compatible with controllers like TF801, TF802, TF804, and TMO720. It has side-on viewing with a light sensitivity of >10 Lux.

    I just want to confirm whether the photocell is working so I can rule it out as the issue in troubleshooting. How can I simulate its function to check if the Satronic MM87 controller recognizes a flame signal? Would using a variable resistor work, or is there a better method?

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