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Dunkirk Boiler Not Responding to Call for Heat

wrightej Member Posts: 2
I'm looking for some guidance with my Dunkirk DKVLT-150 gas boiler that controls radiators in my home. I recently attempted install a Nest Learning Thermostat, realizing that I did not have a C-wire I purchased a plug in 24v transformer and wired it through the Nest Power Connector following the below:

I don't seem to be getting enough power to the nest thermostat. Somewhat more concerning is when I went back to a traditional thermostat the call for heat does not seem to register. The boiler is still working when domestic hot water is called for and I was able to set it into CH Mode 3 which is a CH with Permanent Demand which basically goes to set water temperature and ignores a thermostat, so I know the issue is just controls related.

Looking for help troubleshooting the original battery powered thermostat so my system properly calls for heat, could I have tripped the control board somehow by sending power back to the dry contacts? Secondly, I would then like to understand proper installation of the Nest thermostat.

Below is a picture of the wiring into my control panel. Right now the red/white on the bottom is going back to the W/E (white) and RH (red with jumper to RC) on the thermostat.


    HVACNUT Member Posts: 5,870
    An blown fuses in the Dunkirk board?
  • wrightej
    wrightej Member Posts: 2
    I’m not sure, where would I check for those? I am not getting any error codes on the boiler.