There is no remedy!!!
I have a CSI 120 LOW NOX which intermitently fails on a code 14.
I have replaced the ignition control board ,potentiometers,DHW and CH sensors etc etc and I still have the problem.
The system was powerflushed before installation and again recently so a dirty system is certainly NOT a factor.
When the boiler actually works its certainly cheap to run and produces hot water quickly and in abundance but this code 14 fault is the bane of my life ANY IDEAS??
DAVE, January 2010