connecting tado starter kit v3+ wireless wsmart thermostat to Vaillant ecotec pro 28

hi wonder if any can help loads of vids on how to connect tado to boilers except for the vaillant ecotec pro 28 can any help me please - In the instructions under combi boilers i believe for 230v i need to use switched live so i hope someone can confirm this - im having trouble understanding replacing wiring direct into the boiler which has a circuit board on it with programmer timeswitch 150 can someone advise whereabouts to connect on this board as it is somewhat confusing - more specicially where (n - l - com - nc - no) are shown in the circuit diagram thanks and regards john