problems with baxi bermuda

[livewire]

hi im having problems with an old baxi bermuda gas boiler heating system i seem to get violent bubbling occurring in the header tank every twenty minutes or so i have tried bleeding radiators and closing down radiators because i thought it might be a slugge problem it seemed to work for a while but the problem has started again i also get radiator doen stairs going cold at the bottom has anyone got any ideas thanx

 

[corgiman]

have you checked the pump?

 

[namsag]

Violent bubbling into header tank indicates your boiler thermostat has gone. Get it looked at asap .