boiler problems

[Hiss]

would anybody have a clue why my gas combi boiler won't stay lit after igniting??? all other gas appliances are fine but the pilot light in the boiler will not continually stay on unless you have your finger on the ignition switch.

[matt1e]

knackered thermocouple probably

[davewr]

The pilot light jet could be partially blocked causing the flame to be too small to register with the thermo-couple.

[fadeout73]

Get boiler engineer out. It is probably a valve. I had this problem just before christmas

[Rev. Green]

The same fault on mine was caused by the bypass valve (next to the hot-water tank) being closed. I replaced it with a sprung-loaded one, but open the valve first to check if this is the fault.

[Disco Fever]

Deffo sounds like a knackered Thermocouple

[Hiss]

thanks everybody for your input

[gucciman]

new thermocouple needed, or pilot injector and tube needs cleaning out, or faulty gas valve.