Wiring a horseman 425 tiara

[Jimmy P]

Hi,I wish to change a 600 switchmaster heating timer with a horseman 425 tiara.i have connected all the wiring as per instructions.i have however noticed a loose yellow wire on the switchmaster,it looks like it should be connected to term 3 . Is this correct. And when I get round to changing timer,where would this wire go on the tiara.i am guessing this wire may be to the motorised valve.is this correct and thanks for any help.jim

 

[ShaunCorbs]

What terminal was it in on the old one ?