Hi I have an old Apollo 30/50b boiler that has worked ok for a while however recently when it is switched to the high thermostat it is making lots of strange noises. It is making fizzing sounds and generally being noisy with occasional loud bangs which it didnt before.
I have already changed the pump, mid position valve cleaned the system with Fernox and cleaned out all the radiators (which didnt have too much black sludge in). The system is gravity fed and 8mm microbore.
The boiler runs ok on the low thermostat apart from being a bit noisy when cold. The hot water and radiators all work as they should but we will want it on high at some point over the winter!
I have been told to try cleaning the system again as it could be crud that is stuck in the boiler but im not sure if this will fix it.
Does anyone else have any suggestions? It seems to me like the problem is with crud in the heat exchanger not the rest of the system. Can the heat exchanger be cleaned?
Thanks...
I have already changed the pump, mid position valve cleaned the system with Fernox and cleaned out all the radiators (which didnt have too much black sludge in). The system is gravity fed and 8mm microbore.
The boiler runs ok on the low thermostat apart from being a bit noisy when cold. The hot water and radiators all work as they should but we will want it on high at some point over the winter!
I have been told to try cleaning the system again as it could be crud that is stuck in the boiler but im not sure if this will fix it.
Does anyone else have any suggestions? It seems to me like the problem is with crud in the heat exchanger not the rest of the system. Can the heat exchanger be cleaned?
Thanks...