Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

Buderus GB142/30 no fire on initial start-up

fosterdl Member Posts: 21
I just installed a new Buderus GB142/30 for a customer. This is my fourth Buderus  install, so I'm new at this, but every other GB142 I'veinstalled worked fine from the start. My problem is  that when I went to start it, the intake fan ran to purge the combustion chamber and then it did nothing after that. I'm not getting an error code, but the LED gives me the temp (63 deg F.), water pressure (P19) and OH indicating that the unit is ready to run. However after several attepts it won't respond to the stat calling for heat. Any thoughts?


  • Slimpickins
    Slimpickins Member Posts: 326
    end switch

    Are you doing DHW as well and still not firing? Did you keep the old zone valves? You may have a bad end switch, Jump the thermostat connections coming out of boiler to see if that fires it. Other than that, get the service manual and bust out your volt/ohm meter and go thru it. The service instructions are pretty good if I remember right.
  • fosterdl
    fosterdl Member Posts: 21
    End switch?

    Not sure what the end switch is, but I'm sure I'll find out. No DWH on this install. I did jump the RC1 and still not fire. Yeh, I looked at the manual this morning. It looks pretty thurogh. I'm using an Argo ARM2 but I by-passed that and thinking the remote switch circuit might be bad, but still no luck. My service tech gut thought it might need to be "burped". I jumpered the circulators to run constant, and still nothing. Can I loostn the air bleed at the top of the heat exchanger to purge it? I wouldn't take it off, just enough to bleed some air if present.
  • ColoradoDave
    ColoradoDave Member Posts: 54
    Boiler Trigger

    Not sure what an Argo ARM2 is, but if you're using an external dry-contact (no voltage) switch, don't you want to connect to the WA terminals?  I think RC on the Buderus is for their Remote Controller for indoor reset.
  • fosterdl
    fosterdl Member Posts: 21
    You are correct

    Yes, today I went back to the job and mulled over the schematics again. I noticed that some configurations used the RC terminals. Once switched, the boiler took of and runs great. Lots to learn on the units. Thanks for all the input.
This discussion has been closed.