Help with a viessmann Vitola-biferral boiler

PatQ

Help-I am a homeowner in western Mass and heating guys who know Veismann are very few. The original installer is no longer in business.  I had a guy come out and service the boiler. He replaced the damper which was a six inch damper on a five inch flue pipe. Symptoms: hard start-it takes 30 seconds for the propane to ignite and i get a blow pop like when your gas stove does not start initially. I opened the damper all the way and the pop noise is gone. I called tech support and they said to check the ignition for the propane, my heating guy said he did that, I have no idea if he did or not. The boiler makes a whirring noise for about 30 seconds and then the propane ignites.  Could it be a problem with the Trimatik reading whatever it does.  There are no obstructions in the flue pipe, Is the draw too strong for it to light? Does anyone have any idea what is the problem? I am stuck because it appears that not alot of guys know about Veismann.I know that I cannot leave the damper open all the way as a temporary fix-can anyone out there help me?

Paul Pollets

Burner?

What burner are you using? Reducing the flue outlet is not a good idea unless the chimney is tall enough. Has someone measured the draft or inlet gas pressure? For tech help, try James Brown at the RI office.

http://www.viessmann.ca/aa/en_ca/service/contacts/support.html