I have a oil fired utica boiler that experience delayed starts intermittently.
I've cleaned fully, replaced the air tube assembly (which include igniters and nozzle), and filter.
It starts ok sometimes but at times starting is delayed causing smoke and a boom from to much oil being dumped in the chamber.
Last time this happened (about 7 years ago), we replaced the transformer which fixed the problem.
Is there somewhere else I should look or just replace the transformer?