Mechanical to digital home heating control help

[househelp]

Our flash timer switch for central heating broke!

I got a digital programmer to replace the flash timer. I was doing the wiring and have gotten to the point where the heating can stay on however I cannot get it to turn off! I gather it's to do with my wiring!

Attached is what has been done so far....if anyone can lend some advice please it would be great....the cable coming from the isolation switch is a 3 core....the one going out to boiler is a 4 core...

 

[John Gasman]

From Isolation switch to backplate: (3 core)
Earth to Earth Terminal (yellow/green)
Neutral to Neutral Terminal (blue)
Live to Live Terminal

To Boiler from back plate: (4 core)
Earth to Earth Terminal (yellow/green)
Neutral to Netral Terminal (blue)
Permanent Live to Live Terminal
Switched live to Terminal 3
Link with from Live Terminal to Terminal 4

If boiler constantly firing, you may have switched live and permanent live to to boiler reversed

Always use safe electrical practices, and safe isolation of circuits before attempting this type of work

 

[househelp]

Fair play. That was spot on. Thanks for that

 

[John Gasman]

Most welcome!