Ideal Icos he18

[shambolic]

Actually you should use five connections this helps with the power supply to the boiler switch live!
You have main L3 N and E
Then switched live L1 from boiler to common on programmer then switched live L2 back from CH on(from endswitch) to boiler.
You can however "get away" with only using 4 with just the power coming back down the switched live.

 

[adwt2004]

So if five connections should be used (They are I've checked the connections) then do I just need to rejoin link 6 on the honeywell board to stop the pump constantly running?

 

[shambolic]

Dont know about honeywell wiring centre only know about boiler connections and that it doesnt have or need a pump overrun to dissipate the heat from the boiler