DIY Doctor UK DIY Forums

Hi everyone this is my first time on this site, i hope someone can help me. I have a baxi burmuda with 6 rads and the boiler even turned right down is bubbling as it burns. I can only guess this is a case of bad circulation, i can fear the pump running and the water running through the pipes, so the only thing i can think is a sludge problem. I read another post about sludge problems and sentinel x300 was used should i go this way? your thoughts would be appreciated. cheers

If you can "hear" the water running through the pipes suggests that air is trapped in the system. Normally circulation is silent and any noise is actually water trickling past airlocks.