sorry to ask the same old questions again. Im due to replace an icos 15 he and im looking for your valued opinion. I fit a lot of logic plus combi's , but the heat only requires a wire to the pump from boiler (for the pump over run) I think i read somewhere that this is not required anymore, does anybody know if this is true? Otherwise, what would you put in? It is for a landlord, so price is always an option. thanks..