Hive wiring receivers

[John Nelson]

Hi struggling to wire receiver. Last thermostat had just a live and neutral and boiler on constantly
Any help !

 

[EFLImpudence]

Last thermostat had just a live and neutral and boiler on constantly

Do you mean it had just two wires or three? Not counting Earth.

 

[John Nelson]

A live and neutral and earth was attached The last thermostat was only live and neutral !! Earth was inside the cavity wall earthed. The heating is permanently on full time !

 

[John Nelson]

The third wire wasn’t used in the last thermostat and I attached that to the on no 3 on the receiver

 

[flameport]

The last thermostat was only live and neutral !!

Impossible.
Live and switched live perhaps.
The third unused wire might be a neutral - or not.

A lot more information is required - such as
which hive - there are several
make/model of old thermostat
make/model/type of boiler
any other controls such as timer, programmer, etc.

 

[John Nelson]

It’s the latest hive WiFi receiver. The old thermostat was a Honeywell cmt 907a

 

[John Nelson]

The boiler is permanently on at moment !!

 

[EFLImpudence]

Is this the same as the diagram for your Hive?

 

[ban-all-sheds]

Last thermostat had just a live and neutral and boiler on constantly

Wasn't that a bit of a pain?

What research did you do to establish that swapping to a Hive was the way to fix that problem?

A live and neutral and earth was attached The last thermostat was only live and neutral !!

As has been pointed out, that cannot have been the case.

The heating is permanently on full time !

So no change then - that's how it was when the old thermostat was in use.

It’s the latest hive WiFi receiver. The old thermostat was a Honeywell cmt 907a

Did you check that the Hive was a suitable replacement, and that you knew how to wire it up?

 

[stem]

Hi struggling to wire receiver. Last thermostat had just a live and neutral and boiler on constantly.....The boiler is permanently on at moment !!

I assume by this, that you mean that the original thermostat was working OK, and that it's only since you have tried to install the Hive receiver that the heating is on permanently.

For it to work properly, the old thermostat would have needed two switching wires. Possibly a 'live' and a 'switched live' as has already been stated. [Note. Some boilers can use 24v for control, so in that case 24v switching wires would be used, and there may not even be a live present] Because the Honeywell is battery powered, and does not require a mains supply to operate, sometimes installers use a blue or black wire that would normally indicate a neutral, for a switching wire. So what you may think is a neutral wire because of its colour, might not actually be one. Electrical testing of the wires in question would be required to confirm.

If the aforesaid wires are actually switching wires (230V or 24v), they would have been connected to terminals A & B as per the diagram below, so that when the thermostat called for heat, they would have been electrically connected together. Something that you obviously would never do with a 'live' and 'neutral'.

If this was the case, and there is not actually a neutral present, then you cannot just swap the Honeywell for the Hive receiver without installing some additional wiring. The Hive needs a 230v supply to operate, the Honeywell doesn't it has batteries to power it.

If you could answer @EFLImpudence question about the version of the Hive you have, explain where the wires were originally connected at the Honeywell, and where they are currently connected at the Hive, to help us figure out why it is permanently on, that might help.

 

[Taylortwocities]

Disconnect the wires from the Hive and insulate them. Does the boiler still run?

 

[ericmark]

I have not seen a boiler where one opens the circuit to make it run, so yes I would agree start point is simply disconnect and see if boiler stops. 3 days ago I would have said remove batteries from thermostat and see if it switches off, however just fitted a new thermostat and found I can select with jumpers if heating uses N/O or N/C contacts, so that is not a fool proof test.