Replace honeywell cm907 with Hive heating single channel

[Seb82]

Hi,
I'm looking to replace my Honeywell CM907 thermostat (see attached pictures of the wires) with a Hive Heating, my combi boiler is Potterton Titanium 28.
How to wire the 3 actual wires to the Hive receiver (the grey, unused, is behind the brown and black)?

Thank you for the help.
Sebastian

 

[stem]

The two wires now in Honeywell thermostat A and B go to Single Channel Hive terminals 1 (Common), and 3 (Heating on)

However, your existing thermostat is battery operated, but the Hive is mains powered. So in addition, you need to connect a 230V supply to the Hive receiver N and L. This should come from the same fused connection unit that is supplying power to the boiler, so that when the boiler supply is switched off, the Hive is also.

Terminals 2 and 4 aren't used.

 

[ericmark]

Flowing from @stem why do you want Hive, Nest e is the only battery operated base I know for a wireless thermostat.

 

[Seb82]

The two wires now in Honeywell thermostat A and B go to Single Channel Hive terminals 1 (Common), and 3 (Heating on)

View attachment 186138

However, your existing thermostat is battery operated, but the Hive is mains powered. So in addition, you need to connect a 230V supply to the Hive receiver N and L. This should come from the same fused connection unit that is supplying power to the boiler, so that when the boiler supply is switched off, the Hive is also.

Terminals 2 and 4 aren't used.

Thanks
If the grey wire is the neutral and the brown is with 230V should work?

 

[CBW]

Is that where you want the receiver? If yes,it could possibly work.

 

[Seb82]

Yes, the place for the receiver.

 

[CBW]

Should work then if that’s the neutral. Need a link from L to common

 

[stem]

Some boilers are wired to use either 230V or 24v for their control circuits; so in the latter case it wouldn't work [although, I think from memory your boiler is 230V only] If you use a multimeter to test between the brown and grey wires, it will soon show if 230V is present there or not.

If your boiler has an internal timeswitch, that will need to be set to be permanently on to provide power to the Hive receiver.

 

[Seb82]

Yes, is 230V between brown and grey, also same 230V between brown and black. So will work to wire the Hive receiver?

 

[stem]

Yes, is 230V between brown and grey

That's what you are looking for. Don't forget the link as informed by @The Novice.

Should work then if that’s the neutral. Need a link from L to common

 

[Seb82]

Thank you for advice, very useful.