Starting a Myson Apollo boiler after gas supply failure?

i have an apollo 40 b room sealed which the pilot keeps cutting out,i have changed the thermocouple and the overheathermostat as well,nothing has changed,shall i change the gas valve or go for a new boiler seeing that the boiler is 20 25 yers old and because probably is full of limescale gets too hot and cut the boiler out.thanks a lot

maurizio
October 2007

Mine's an Apollo 15/30b. The procedure for lighting this is as follows:
Press in and hold the big grey button for a few seconds, then press the electronic ignition (may need a few presses).
Once the pilot is lit keep the grey button pressed in for about 15-20 seconds then release it slowly. If it goes out then turn the grey button clockwise and release; then start anew after 3-4 minutes.
If the pilot stays lit then put the thermostat onto high until the burner fires up. After a minute or so, switch the thermostat to the desired setting.
Note; the instructions on my boiler say to do this with the mains off but I've found it makes no difference.
Hope this helps.

Supercrump
August 2005