I doubt the word of the manufacturer's agent - not what you wrote - no wish to offend whatsoever.
I shall continue to try to be clever wherever I wish - it's my own personal tragedy sadly.
In the world of heating boilers much rubbish is spoken - most of it by me I grant you - but I'm pretty sure that domestic boilers are unlikely to experience a software fault.
Doubt everbody and question everything - has continually got me into trouble.
Once again - sorry if my comment grated with you...I lack interpersonal sensitivity.
Merry Christmas...
Peccavi - unbowed, December 2009