powering nest thermostat from heating wiring help

[motofox69]

Hi ive kind of successfully installed my nest learning thermostat in place of the old honeywell programmer and thermostat however, i wanted to use the existing wiring from the old thermostat to power the nest thermostat. To do this ive fitted a mains socket next to the juction box upstairs in the airing cupboard and used a 12v transformer to power the nest . ive tapped the power off what i thought was a permanent live in the juction box but it seems to turn off only when the hot water is turned on thus turning my thermostat off.

Is there a way for me to get a permanent live to this socket, when the heating is on theres like 4 lives, could i jump the live from another

Attched is a photo of my juction box showing where ive tapped the into the live which is turning off. i belive this is a y type system.

thanks

 

[muggles]

Why didn't you just join the existing thermostat wires into the Nest power supply in the Heat Link? Saves a lot of fannying around with sockets and transformers

 

[motofox69]

because the heatlink is down stairs and the thermostat wires ended up stairs

 

[muggles]

Not sure I follow. I always wire the Heat Link into the wiring centre when I'm installing Nest. Have you put it somewhere else?

 

[motofox69]

i replaced the programmer with the heatlink which is next to the boiler in the kitchen, and the watertank and stuff is upstairs, the old thermostat wires end up stairs too.

 

[muggles]

That's where you've gone wrong and why you're now struggling then. Heat Link should go in the airing cupboard upstairs. Move it up there and all will be well