I have fitted a Hive single channel thermostat to my Worcester Greenstar 32CDi boiler to replace the existing Comfort II RF thermostat.
I removed the link for the Central Heating in the boiler thinking that would disable the old thermostat.
However it seems that they are now working in series. If both thermostats are ON, the heating will be ON. But if either thermostat is OFF, then the heating will be OFF.
Can anyone please advise what I should do to properly disable the old thermostat.