My clas 30 he ariston boiler as stop working and is flashing err 501 can any one help thanks

Lee, October 2013

I got same problem..
Replaced the main PCB £170... still got the same error... now going to try these in accordance with Aristons support:
Check the earthing to the unit
replace the 60000867-01 and then 60000868-01 (should have tried those first as they are only £25 each!!! Ariston dont tell you that though - not sure why ;)

Craig, November 2013