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Ignition problem with UB95M-200 Boiler
I have a problem with my UB95M-200 boiler, and it sounds very much like a past dialogue I found on your site https://forum.heatinghelp.com/discussion/144579/utica-boiler-ignition-problem
My brother has the identical unit at his home, and I have swapped the spark plug, spark plug wire, and the control module — one at a time — and I still get a 02 error on my unit, and my brother’s unit runs fine. Also, the rumbling sound that was mentioned in the previous post (link above) has been happening in my unit for the past ten years. The installer technician could never figure out why it was happening, and finally gave up trying about seven years ago. Despite the crazy sounds upon ignition, it has kept my house warm for the past decade. Now, after resetting it will not ignite. Twice in the past week it ignited and warmed up as normal, only to fail in a subsequent cycle and stop with the 02 error showing after five attempts at igniting. Help!