Wiring a heatmiser UH4.

28 Mar 2021
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United Kingdom
Hi I have a valiant protec 28 combi boiler and is wired thru a honeywell 10 way junction box. I have to add some new zones so thought of getting a heatmiser uh4 wiring box but I am confused as to how do I migrate the wiring connections from the old to the new heatmiser UH4. All the connections seem to be easy but I can't figure out these 2.
1. BOILER CONNECTION: On the old wiring junction from the boiler I have 5 wires coming. 2 wires, black and brown connected to line, blue is in neutral and green goes to earth and then there is a grey which is connected to the honeywell 2 zone valve orange wire. So on the heatwiser, where would all these wires go as it shows in the diagram for boiler there are 3 ports LS, E & LR. Do which 3 and what happens to the other 2?

Point no.2: on the heatmiser where it says connect UFH pump, you can connect the 2 port zone valve as well. The pump has 3 wires which are simply L,N & E and on the UH4 it clearly indicates LNE so I connect it there and when the thermostat starts I see the pump starts and when thermostat off it turns off. But the 2 port valve has 5 cables I connect L grey N blue E green as that's how they are connected in the old junction but the it has additional 2 wires orange and light brown where do i connect them in the UH4? In the old box the orange is connected to the boilers grey wire and the light brown is connected to one of the thermostats wire.

Please advise where would I connect these wires.

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