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NTI - Trinity Ti - Boiler stays on

tyalkin Member Posts: 1
edited January 2015 in Gas Heating
I'm having trouble with my NTI - Trinity Ti boiler.

Even when I disconnect all the wiring connections (i.e. the wiring from the flow switch, thermostat, and outdoor probe), the boiler stays on.

I tested the voltage on the ports to see if there was a current running through them. It turns out that there is just over 20 V running through the ports for the flow switch when I connect them using my volt meter. I'm also getting a small reading when I connect the ports for the outdoor probe.

I'm not sure what the problem is, but it seems like there might be an internal short on the wiring leading from the probes, into the boiler, for the flow switch.

Has anyone encountered this? Does anyone have any thoughts? Thanks so much in advance.


  • NTI- NYThermal
    NTI- NYThermal Member Posts: 1
    So sorry you are having issues with you Ti
    Have your contractor give our technical support line a call. They will work with the contractor to effectively diagnose the problem. Toll Free: 1-800-688-2575 dial 2 for technical support
  • icesailor
    icesailor Member Posts: 7,265
    Have you checked the polarity of the electrical supply to the boiler?

    Do you have voltage on the neutral or earth ground?

    Bad neutrals can be a serious problem. Especially in old houses.

    I've seen where water "wicked" UP the service wires on a outside weather head, ran through the inside of the service drop, and came out and dripped on top of the buss bar on a panel. Especially on old paper SE cables with panels with the buss bar on top. Maybe that's why in Canada, they seem to mount panels on their side.

    If you are brave, take the panel cover off. If you see any signs of corrosion on top of the buss bar, Do NOT FTI. Call your friendly Sparky for assistance.

    If you have a house with old two wire ungrounded outlets, or ones that were changed to 3 prong plugs with no ground, don't even futz with anything until you have Sparky test the readings on the black and white to the boiler for proper continuity.

    And call NTI-NY Thermal too. Its nice to know that Reps read this board and see some of the things we run into. So when they get a cold call disaster from someone who knows, they will think about whether someone is blowing smoke or not.
  • unclejohn
    unclejohn Member Posts: 1,749
    Some boilers come out of the box set for a minimum temperature. You may have to change the set up of the control.