Google Nest Community

https://widgets.nest.com/nest-thermostat-troubleshooter/?hl=en#e89

Thanks Mike,Very good , pictures are legible 

Hello Mike,Can you zoom in before you take pictures. The clarity is blurred. Thanks

I will feed the spst relay from load side of 24 vac transformer. The T terminal of boiler will feed through relay normally open contacts, will close on demand from Nest thermostat, to cause boiler to turn on for heat. The same scenario will apply to ...

I will pull back the existing two wire cable and replace with either a 5 or 7 conductor cable to feed the Nest thermostat. Thanks for your helpI will install 24vac xfmr along with relay at the boiler control box.