Help Replacing Honeywell St699
 

Hi all.
I need some help replacing my old honywell st699 with a new st6300a. the problem is that i have the new installation guide telling how to replace the 699 with the 6300 .
ie
st699 to 6300 L to L , N to N , 3(no) to 4(ch on) , 4(nc) to 2(ch off) , 5(com) not connected , 6(no) to 3(hw on) , 7(nc) to 1(hw off) , 8(com) not connected.

now in my 699 number 8(com) is joined number 5(com) which are then wired to the live.. and there is no wire going to 4(nc) so was wondering where to put wire these up to in the 6300.
any ideas..