Horstmann 425 diadem to hive

[Redd33552211]

Trying to convert from a Horstmann 425 diadem to a hive system. Although the wiring is completely baffling me. Any help greatly appreciated.

 

[Exedon]

From left
Earth neutral permanent live switched (timed) live.
Ignore the brown links.
What boiler do you have?

 

[CountryFan]

Have you got a single or dual channel Hive?

 

[Redd33552211]

Thanks for reply. It’s an oil boiler and I have a dual channel from previous house.

 

[CountryFan]

What does the Horstmann currently control? Looks like only one, hot water?

 

[Redd33552211]

What does the Horstmann currently control? Looks like only one, hot water?

Yep hot water, but radiators heat up when it is on.

 

[polesapart]

https://www.tlc-direct.co.uk/Technical/DataSheets/Horstmann/425_I.PDF

 

[ericmark]

As said yours seems to be connected DHW only so not sure if you should use terminal 3 or 4, I will have a guess running some sort of C Plan? What motorised valves do you have if any, the C Plan normally no motorised valves, and it runs just boiler for DHW and boiler and pump for CH, the Hive has a software fix, so it is one of the few that can work C Plan, Wiser does not have the software fix.