so i managed to get the hive to work perfectly with my system thanks to Stem's help
i am now thinking of removing it and going with a google thermostat, purely because everything is google in my home, i didn't realise that google actually did a thermostat when i got the hive.
is it possible to use the google thermostat with my back boiler system?
google help is absolutely terrible.......
Right hopefully i've got this right.
The programmer should still be completely wired up and switched to always on.
and i only use the wiring for the T40 honeywell thermostat.
The L (terminal 1 ) on T40 goes to C on the nest E
the switched Live (terminal 3 ) on T40 goes to NO on the nest E
ignore the Neutral on the T40
Thats how i've wired it and it seems to work ok so far