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Ultra + manual reset

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bovide_4
bovide_4 Member Posts: 161
in Thermostats and Controls
Good evening. Last week I had to troubleshoot a Weil McLain Ultra, 3 years old. The DHW circ. was not functioning.The cylindrical fuse was jumped, and the flat fuse was blown. When I disconnected the manual reset high limit,(Honeywell L4006E), the circulator turned on after replacing the flat fuse. The L4006E shows no continuity resistance. The manual reset is wired to the terminal strip for external limits. Also, the external manual reset aquastat is required by code here.

When I reconnect the aquastat, the Ultra locks out on "Limit Open". Any ideas?

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  • Paul48
    Paul48 Member Posts: 4,469
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    Try

    Disconnect the wires from the hi-limit and twist them together. If the unit runs, the resistance in the switch is too high for the circuit.
  • bovide_4
    bovide_4 Member Posts: 161
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    I did

    I did, and no lockout. Is there an alternative high limit manual reset I can use?
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