Our house is about 30 years old and for the first time in at least 2 years (since we bought it) we lit a proper fire (coal etc) last night, everything was fine until about 11.30pm when we heard a bubbling noise from the fire (figured that's the water in the back boiler). Then all hell broke loose it sounded like the walls were going to explode with the amount of creaking going on in the walls. Now I assume this was just the pipes expanding etc but it really sounded like there was heavy construction happening. My wife though the walls were going to explode.
Can anyone tell me if I have anything to worry about?
If the steam pipes, at least horizontal runs, have sagged then water from condensing steam can collect here and there and as steam blasts through to get to the radiators you hear clanking and banging noises.
If you know where there is a sagging section of pipe, sometimes setting a radiator up on small wood blocks will cure the problem at that spot.
But you need to be sure that the problem is not due to overpressure in which case you need to kill or reduce the boiler fire and let it cool down.