Gas and Oil Home Heating Furnaces - flame roll out

I have a hot water boiler for radiant heat in my house. the flame roll out fuse was tripped. I checked the flue and everything seems ok I took the flue out to see if the problem was in the chimney or in the boiler and it's in the boiler. what can be causing the flames to roll out like that all of the sudden? please help it's pretty cold in the house

On the first start up of the year, try opening an outside door for a few minutes to get a good draft going at the boiler when you fire it. After that, see if it then operates normally. I've seen people use their fireplace before using their heating system for the first time of the year and cause a back draft in the furnace or boiler. A hot water heater or cloths dryer might cause this also. If that doesn't help, then you might have to look into a cracked heat exchanger or something else. Let us know.

there is a lot of soot all over the bottom of the heat exchanger i'm cleaning it all out right now. it kind-off makes sense that all the soot wouldn't let the flame escape properly, and cause it to roll out

it was the soot after all. it's a messy dirty time consuming job but everything is fine now

Everything is not fine just yet. You need to fix the problem that caused the sooting or it will happen again. See the other post.