Battery thermostat to Hive mini wiring issue

[RichHaddon]

Hi all.

Got an issue with an upstairs thermostat I'm struggling to wire in.

Current setup is Hive down stairs controlling the downstairs heating and hot water and a Myson battery powered thermostat upstairs controlling just the upstairs heating. The Myson upstairs had 2 wires going to it a black wire with a brown sleeve and a brown wire. There is also and unused grey wire and earth wire which was not wired in at all.

New setup was to use a Hive mini I managed to get power to it and connect it up to app etc but no joy getting it to talk to the boiler (conventional). Using black wire with brown sleeve to Neutral, brown to live with link from live to no1 also, Grey in no3 and earth to earth.
I don't think the grey wire is connected anywhere.

Any help would be great as I believe I'm close but missing the last step.

Thanks
Richard

 

[ianmcd]

Using black wire with brown sleeve to Neutral,

well that is completely wrong the brown sleeve is telling you ir is a live wire, the Hive mini does not use a neutral it has a live and a switched live, it is battery powered and is simply a switch

but no joy getting it to talk to the boiler

It doesnt talk to the boiler , it controls a zone valve, that zone valve talks to the boiler

 

[RichHaddon]

Thanks for the reply.
So the reciever for the hive mini is wired Is what I'm referring too.

I have attached a picture of current setup. As I say it powers up and connects but will not activate the zone valve

Thanks

 

[RandomGrinch]

I have attached a picture of current setup. As I say it powers up and connects but will not activate the zone valve

As above, your wiring is incorrect - in general, mistaking a switched live wire for a neutral, is asking for a really big bang!

The black (oversleeved brown) wire, is the switched live returning to the zone valve.
This should go into Hives terminal 3.

The Hive is currently powering up, because the switched live is acting as a 'false neutral', connected to true neutral through the resistance of the motor in the zone valve.

You need to repurpose the light grey wire as a neutral, within the wiring centre.
There appear to be two greys connected together in the last terminal?

Are you able to trace these back to the thermostat cables?

 

[RichHaddon]

Thanks for the detailed reply.

I think your right I need the grey wire to act as the neutral. I'm not too sure at this point how to trave it back from the busy wiring centre.
Thanks for pointing me the right way though. Appreciated

 

[ianmcd]

I think your right I need the grey wire to act as the neutral.

NOOOOOOOO the two grey wires are permanent lives, DO NOT attach them to any Neutral

 

[RandomGrinch]

. I'm not too sure at this point how to trave it back from the busy wiring centre.

I'm fairly confident that the grey wires, highlighted earlier, are spare and parked in the end terminals.
If you follow the black wire (circled red above, and connected to what I believe is a brown to a zone valve), you should find the cable from the thermostat.
That cable should include one of the parked greys.
If that is the case, you can find out if this cable is correct, by temporarily disconnecting the black wire (safely isolating it in a spare termiinal) and seeing if the upstairs zone fails to turn on.
The grey wire associated with this cable can then be connected to the neutral terminal, to power the Hive.

If the upstairs zone fails to turn off after removing the black wire, we've got the wrong cable and we need to look again.

Edited for clarity - the wiring centre isn't the easiest to trace connections in.

 

[RandomGrinch]

NOOOOOOOO the two grey wires are permanent lives, DO NOT attach them to any Neutral

We're talking about a different pair of grey wires!
Perhaps whitish grey might be a better description

 

[RichHaddon]

Thanks grinch I will check that first thing.

Just for double clarity which is the neutral terminal if indeed the black wire Is the correct one??

Thanks

Richard

 

[RichHaddon]

Is there any reply to which is the neutral terminal on the wiring centre?

I think I'm good to go after that

Thanks

 

[RandomGrinch]

Is there any reply to which is the neutral terminal on the wiring centre?

2nd from bottom, with the blue wires in it!

 

[RichHaddon]

OK thankyou.
So the correct grey wire couple's up with the 2nd from bottom neutral wire.

Thanks

 

[RandomGrinch]

So the correct grey wire couple's up with the 2nd from bottom neutral wire

? - wires...

 

[RichHaddon]

That's right. So I put the used grey wire in the parked terminal at the top into the sake block as the neutral in the last picture you.have sent?

Apologies for my nievty