I am confused of how I can acheive this with my setup.
I have got a danfoss RX2 that provides the inputs for both heating and room stats (there is no programmer as the room stat is programable)
The connection box RX2 has a zone (zone 2) output that switched live, there is then two other outputs that is switched live (zone 1 on) or (zone 1 off)
The boiler has a live imput that fires the boiler and pump. There is then another input (mains Swl) that is the switched live from the external gravity hot water circuit.
If the boiler is run as fully pumped, it will need to have pump overrun selected - this will need to overrun the heating pump only.
As far as I can make out I need to wire the RX2 outputs from that stat to the pump, and then wire two relays across the pumps (1 per pump) so that when the stat fires the pump, the relay is activated and the "main L" input to the boiler fires". As they are connected via relays the boiler input going live will not fire the other pump.
The problem is the boiler overrun - I cant just wire the hot water pump to the boiler, and ever time the boiler fires the HW pump would run. How can pump overrun be implimented?