Now then Stan, all CDi's inc compact are range rated via the internal software.
On the 34cdi press and hold the spanner button for 10 secs, to access the installer menu, 1A will appear in the LCD display, this is CH power displayed as a percentage of max power (34KW ONLY for HW remember heating is only 30 KW max) PRESS the minus key until you reach the required output as a percentage eg 50% = 17KW, once you have the correct percentage in the display, press and hold the chimney sweep button until brackets appear in the LCD display this takeS approx 5 secs, this stores your setting, press the spanner key briefly to exit the installer menu, JOB DONE!
Don't adjust anything but 1A as some settings can really upset the boiler, hence why this ain't in the install MI's
MODS PLEASE MOVE TO PRIVATE FORUM