Thanks for your reply,the red wire goes to earth,green/yellow goes to the same number as the programmer on the junction box,brown &blue go to the same numbers on the junction box as the midi valve.
Davemac43
April 2011
Confirm that the green/yellow is wired to earth, this would be the one not used in the Honeywell L641, it has no earth fixing point.
Don't just assume, make sure, as you are already aware, you're dealing with 220-240v ac and assumptions can be dangerous/fatal.
Carefree
April 2011
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