Y plan mares

[NICK C SPARKS]

Hi all having trouble with a y plan just moved the old broken time clock from the garage to inside of the house (new clock)
the problem im getting is when calling for hot water we are getting heat into the radiators rechecked the wiring to make sure no wires crossed and all proves ok i have noticed that when the cyl stat calls for heat ( in a timed period) i get 240v to t1 of cyl stat
but then after 5 seconds i also get 110v on t2 that seems to be back feeding down the grey could this be holding the mid position valve open and letting heat into the central heating and if so would be a faultly 3 port valve
cheers for any help

 

[diditrain]

Does the new timeclock have any selector headers that need to be set to your required position. i.e. linked/independant?
Does your valve have a selector lever on it. Had one the other week that was left in the flushing position and causing the same problem