Old Buderus Boiler heat on the stops.

Switchkraft

Hello all. I'm hoping I can get some help. I have a old buderus and the heat was off. I turned the switch off, waited and turned it back on. The burner kicked on and heated to setting temp. After it cools below the setting temp, it tries to kick back on to heat up to the temp setting. It's clicking and trying and won't turn on. I turn off boiler again and the same thing happens, it lights up and heats. Then when it gets cooler then temp setting it tries to heat but keeps trying g to relight about 10 times and stops. What is stopping it from burning a second time around? Any help would be greatly appreciated.  Thank you!!!

Ironman

Uh, gas or oil? How about a model number?

Switchkraft

Gas. 

Switchkraft

Switchkraft

Any help would be greatly appreciated. Thank you for your quick response. 

Ironman

Do you have a DMM and know how to use it? That’s gonna be the only certain way to diagnose what’s wrong.

If had to venture a guess based upon your description, I’d say the ignition control module; but again, that’s a guess, not a diagnosis.

Switchkraft

I'm not sure what a DMM is but regarding the ignition control module, are you saying I may need to change it out? I cleaned the coupling sensor and it worked for a day or two and went back to not working again.

neilc

loose or dirty inconsistant ground at the pilot assembly ?
everything tight down there?

HVACNUT

On the second try, see if the pilot is actually lit, or is it spark only?
If the pilot is lit, then it's not being recognized by the sensor or ignition control. 
If its spark only, you need to see if there's 24v from the ignition control to PV on the gas valve. 

Ironman

Switchkraft said:

I'm not sure what a DMM is but regarding the ignition control module, are you saying I may need to change it out? I cleaned the coupling sensor and it worked for a day or two and went back to not working again.

DMM: Digital Multi Meter.

A proper diagnosis requires one and knowing how to take proper readings along with observation.

Just as a good physician may suspect what’s  wrong with a patient from his description of his problem, he still must do tests to confirm it; so it is with diagnosing an HVAC control problem.

No, I’m not saying change the ignition control - unless a proper diagnosis confirms it.

Jon_blaney

See if you can figure out what is clicking.

Switchkraft

I switched out to a new ignition cord and still the same thing.  I think it may be the ignition control. 

Switchkraft

I'm still looking for parts. I appreciate all your feedback. I'm I'm female trying to learn. Have some hvac guys here and they seem to not really know or are guessing 

TAG

It uses all Honeywell stuff. The thing that says Honeywell is the temp control for the boiler and the relay from the thermostat. Make sure it's not clicking more than once -- they do fail and don't hold down the contact. The relay closes (it under the cover) and it sends the 24v power for the ignition module to start. You should hear the rapid spark and the pilot light through the small window .... after the pilot lights the gas valve will open to light up the whole burner.

You have to watch and listen and see where it not moving to the next step. I'm not seeing any wire to a a vent damper -- does it have ?

I have a couple of them in places and have never replaced a module -- yes for the relay and the vent damper

Switchkraft

Thank you all so very much. What a great forum. It was the ignition control

Switchkraft

Ignition.control.module