Hive to Alpha CB28

[Bleakers]

Hi folks, I think I’m being really dim and would just like to check I’m making the right assumptions.

I have a hive single receiver to install.

The alpha has very simple wiring, the timer sits on the incoming power and will be removed. There is no clock fitted

There is currently a hard wired 3 core thermostat. I think they are just L, N & earth. See the photo.

So I’m taking power from the L & N on the boiler block to the corresponding L &N on the hive backplate, that’s the obvious bit.

However, it’s the thermostat wires. If I’ve interpreted it right in the photo of the existing, it is just a live to terminal 1 on the existing thermostat, neutral to terminal 2. I’m sure that the green/ yellow going to terminal 8 is an earth.

So, I had presumed that I’d just take the live and neutral from the boiler terminals 1 & 2 to terminals 2 & 3 on the hive backplate but researching and thinking it through, that’s wrong and it should be 1 & 3. Earth is not required.

If someone could just confirm, that would be tremendous.

Many thanks.

Bleakers

 

[CBW]

Looks like you’re confusing a blue wire for a neutral wire (common assumption), or that the earth is earth because it’s green and yellow. Wires mean nothing when it comes to heating. Without knowing your existing thermostat, then you need to work out which is live/common and switched live, once this is confirmed, it’s just a case of putting them in correct terminals.

 

[Bleakers]

Chris W, many thanks.

Looking for the model, I have found this.....

So, I think that the brown is in fact live (terminal 1) on the thermostat, green yellow is the switched live (terminal and blue is Neutral?

So, although that should make it simple, I’m not clear how that translates to the corresponding terminal on the hive backplate. Told you I was having a slow day.

The choices are common, heating on & heating off..... So which to which?

 

[Bleakers]

And apologies, should have said many thanks for your help, all who are reading etc...

Bleakers

 

[Bleakers]

And just to make it more (possibly less?) complicated, I have just had a look at the Sunvic select 107 timer which is coming out.

The backplate is shown here. Along with wiring plan off the back of the unit.

So there looks to be a live common at point 1 and a black wire for on at terminal 3.

If I replace this with the hive, I am presuming I could use this backplate location and cable as is. Need to check where the black wire is going in the boiler, which is in the loft, but could this just be used as the on off on the hive and loop out the external thermostat?

Also sunvic now not happy at being removed, busy clicking away......

 

[CBW]

Ok so looks like number 4 on timer is being used to park the earths. Black is switched, does this wiring go to a fused spur or wiring centre of some kind - this links to switched at room stat.

Once all this is figured out, you can do the work - OR:

Put Hive on existing backplate (industry standard) and either set Sunvic room stat to max, or remove existing stat and link the Live and Switched.

 

[Bleakers]

And there’s more,

Black from the programmer is being joined at the boiler to the brown in the thermostat, so we thought that is the live feed to the thermostat.

Blue feed to the thermostat is in the live

Green yellow is returning from the thermostat and connecting into terminal 1 on the alpha boiler.

Question then is do I just remove the thermostat wiring and put the black from the sunvic programmer backplate into the Alpha terminal 1? (This would be the wire that needs to go in terminal 3 on the hive backplate.

This would probably make more sense if you folks were stood looking at it......

Many thanks for any help

Bleakers

 

[Bleakers]

The supply to the backplate comes off a fused spur and is 3 core in and 4 core out

Thanks Chris

 

[Bleakers]

So, re- reading Chris,

Just so we’re talking the right thing, this is a hive receiver, hub and wireless thermostat set...

I’ll swap the backplate for the Hive version, put the earth on the proper earth tag.

Permanent L&N onto the lhs connections, looped live onto terminal 1 on the hive backplate and the black heating on into no 3

At the boiler end, keep all the perm L & N & earth where they sit.

The question is for the black, as I understand, that going to go into 1 on the boiler block, terminal 2 on the thermostat is not linked to anything, nor looped out.

Cheers

Bleakers

 

[CBW]

Going through the photos, that Black wire looks like it’s part of the incoming mains supply. So I’d go with the live and neutral at the timer, using the black switched live and link the common.

 

[Bleakers]

Hi Chris,

Looking at the backplate photo, the incoming supply to the programmer backplate is three core and is the cable on the right as it enters from the fused switch.

The cable on the left of that photo is four core, with the additional black and feeds the power and switched live to the boiler as I’m understanding it.

These look on the backplate to be right I think for the hive receiver unit to be wired the same way.

So the four core goes up to the boiler in the loft. L, N and E are on the left of the photo of the boiler along with the black core, all still held by cord grip. I think the power and earth are all in the correct place. (It’s all working)

The black core from the standard backplate as above is jointed to the brown feed wire to the thermostat

The blue is neutral and connected into the permanent neutral.

The green yellow core returning from the thermostat, marked on the photo is the switched live from the thermostat and goes into terminal 1 on the Alpha block, which is marked as being the switched live room thermostat connection.



So my thinking is that if I disconnect the thermostat wiring and pop the black core from the hive receiver into the Alpha terminal 1, the switched live room thermostat connection?

I’m sorry to be so numpty, I can normally do wiring very easily, but I am struggling with this, I don’t know why.


Many thanks

Bleakers

 

[CBW]

I think that’s right in what you’re saying. However like I said, if you leave the wiring correct at boiler, us the L,N,E at backplate of Sunvic timer, use the switched live at Sunvic, and bridge the L to Common, then just joint the 2 wires at stat end, or leave stat in and set to max.

 

[Bleakers]

Hi Chris,

The old thermostat is coming out, so in the photo, all highlighted and traced in red is going to be disconnected.

The black switched live from the Sunvic / Hive backplate is then connected in as the yellow trace.

The Hive hub and wireless thermostat take over from the programmer and the hard wired thermostat. The receiver replacing the Sunvic programmer essentially then becomes a fancy switch and provides the permanent power to the combi for hot water and a switched live to turn on the heating. If I got that wrong I’m screwed...

I think it’s only going to need the black into the yellow traced connection to replicate what’s there now with the thermostat out of circuit?

There isn’t currently any cable into the second Alpha block connector as per the diagram right at the top?

The live to common in your post, that is in the Sunvic/Hive back plate? If so, that loop is in place.

Not clear which two wires you were suggesting to joint if the thermostat is coming out.

Really sorry to be a pain...

Bleakers

 

[CBW]

Sounds feasible, I think you’re making progress. The 2 wires was at room thermostat end, but since it’s coming out, no need.

 

[Bleakers]

Ok, I’ll try installing the Hive tomorrow, what’s the worst that can happen....

I’m pretty sure that if I don’t connect the black wire, that the hot water will still run anyway, the thermostat was 240 v

Bleakers