Replacing Hive with Nest

[robmif76]

Hi all,

Need some advice in replacing my Hive system with Nest. I had a look in the other threads about this subject on here but have been somewhat confused because my Hive configuration seems different to any of the photos previously posted.

My system has a water tank so I was expecting to find a Hive box with dual channel wiring as described but this is not the case as (1 & 2 are not wired). Additionally I have a British Gas Wireless receiver with a single connection.

Can anyone help with how I need to rewire these into Nest?

Many thanks in advance.

Rob

 

[stem]

Your Hive receiver below is wired as I would expect. Terminal 3 controls the hot water, and terminal 4 the central heating. That's all you need. [Not all heating systems use terminal 1 and hardly any at all use 2. If they are not used now you don't need to worry about them]

So the wires simply move from the Hive terminals to the Nest terminals that have exactly the same function. N & L are self explanatory, but the other terminals have slightly different designations:

The wire presently in Hive terminal (3) hot water on, goes to the Nest terminal (6) hot water call for heat
The wire presently in Hive terminal (4) heating on, goes to the Nest terminal (3) central heating call for heat

The Heat link also requires terminal (L) linking to the two 'common' terminals (2) and (5) [The Hive has these links made internally]

Finally you can connect the Nest thermostat to the Heat link terminals T1 & T2 to provide it with power, or alternatively use a separate plug in power supply for it.

This is a poor attempt to by-pass the thermostat receiver that was in use before the Hive was installed.

The two wires shown, need to remain connected together, but I suggest you tidy it up a bit and improve their connection. They don't have to be connected to the wireless receiver it's just being used as a junction box. Or, better still, find the origin of that cable, remove the orange and grey wires, and then link together the terminals where they have just been removed from.

 

[robmif76]

Many thanks for your response stem that's very clear. I suspected that 2nd box was a shoddy piece of work. Shocking it was British Gas who did this!

Thanks again.

Rob

 

[stem]

Shocking it was British Gas who did this!

Unfortunately that's not the first time that's been said about a BG installation, I suspect that they use contractors, which is not an issue if they are competent contractors.