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NTI Ti-150 Outside Bad Temp Sensor Question ?

moots Member Posts: 20
edited September 20 in THE MAIN WALL

UPDATE - All fixed per NTI (values all set wrong for RES and set point) !!

Having just purchased a house with an old NTI boiler I am trying to understand the role that the outdoor sensor plays with NTI. With an outdoor temp around 50 degrees if I call for heat the boiler cranks right up with an output temp of around 130-140 degrees for the zone. This runs for maybe 15 minutes and then backs off with the NTI no longer firing (gas display shows zero) and the output is maybe 110 or so. The boiler display shows an outside temp of 67 degrees which is not the case.

NTI boiler settings:


The sensor is behind an aluminum shield and does get some sun on it though. If I disconnect the sensor the boiler will run flat out with maximum output but I have not let it go for too long. Also if I dip the sensor in ice water the boiler cranks right up, maybe I need to move the probe ??

Problem is my zone in the house stays chilly at 60 degrees or so.

So is everything normal here or is the sensor going bad ? Seems I should be able to heat up the zone somehow right ?

thanks !