Hi all, got a problem as usual.. installed a firebird enviromax combi 6 months ago been running fine customer happy as larry - till today. Got black smoke coming from the boiler she say's oh dear say's me. I asked if she'd had a delivery recently yes last week. I checked the tank for the usual suspects - ok checked pump pressure, oil flow changed the nozzle checked the flue for blockage no all ok. I know it will have to be cleaned out now but will it continue to smoke till it's cleaned out or am I missing something, I'm quite new to oil and everyday seems to throw up new challenges I've not come across this before oh and yes I set it all up correctly when it was installed I have all the gear to do it, but still learning just how difficult this work can be and not as easy as it seems..........