Weil McLain Ultra 310 that wouldn't lite

Glenn Harrison_2

had a customer call with no heat in one half of the house. We had installed an Ultra 310 about 1 1/2 years ago which had run flawlessly till he called. I checked the boiler and found it in flame failure lockout. I reset it and it either would not lite at all, or would lite for a second and go out.

After checking the burner electrode, heat exchanger, gas preesure, flue pipes, I wound up calling tech support for some assistance, as the only thing I could see that seemed out of place was a rubber/neoprene type of material that was oddly shaped at the air inlet of the venturi assembly. The gentleman at tech support went out to the assembly line and confirmed that there is supposed to be a flexible seal at the air inlet of the venturi.

I ordered a new gas valve assembly with venturi, which I replaced and the boiler is running fine. Apparently this missing seal was allowing way to much air to mix with the gas and prevented ignition.

Below are pictures of the old and new venturi assemblies.
I thought everyone would find this helpfull and interesting.