my myson apollo 30/50 boiler keeps cutting out.I have recently replaced the thermocouple and the limit stat .I can get pilot to light burners fire up it starts making a whining noise nd after about 10 minutes it goes off completely. I`d appreciate any help or advice.it is old but just need to get through another 12 -18 months before replacing. l

peejay, March 2010

check the pump is running.

Ian, March 2010

check if there is fan and it may be this making noise, or if no fan than boiler may be overheating in heatexchanger.

k, March 2010