Potterton combi boiler and hive thermostat Install

[Allan9]

Afternoon Everyone

I have a Potterton titanium combine boiler with a very old thermostat and I tried to upgrade the thermostat to a Nest generation 3 and I got a little confused with the wiring so I put it all back as it was and decided to ask for advice.


original connection setup has a direct feed from a fuse spur and a wired thermostat in the room, so I looked at the boiler connections and that has 5 wires 3 for the live, neutral and an earth the other two wires go to the thermostat and just make a connection to turn the heating on, I have the boiler on constant not on the built in manual timer so that all is controlled via the thermostat.

That’s the easy bit, now to the tricky bit for me anyway

The Nest has a power feed live and neutral from a fuse spur I’m happy with that but if I feed that how do I get power to the boiler? Do I put two lots of wires into the hive one is the feed and the other to the boiler or is there another way?

And then where do I fit the old thermostat live wires to the Nest?

I have attached photos of all info I have but it is baffling me how I get power sorted any help with this would be very much appreciated.

 

[ianmcd]

what Hive have you bought ? single channel or dual channel

 

[Allan9]

As far as I can tell it the new duel channel version 2.4 and 5ghz from screwfix

 

[Allan9]

I’m putting it onto a stand so don’t need to wire in T1 and T2 will be using usb

 

[Allan9]

Oh it’s just a single zone I’m only using it to control the front room the rest of the house will be on radiator tvr valves

 

[imiller9]

Sorry, you’re saying fitting hive, but the instructions you’ve posted are for Nest, which is it
H

 

[Allan9]

Sorry yes it is a Nest thermostat i have purchased I can't seem to change the header to Nest

 

[stem]

The thermostat wires presently in the existing room thermostat terminals marked L and SL are rerouted to The Nest Heat link terminals 2 & 3. Ideally, because the blue wire is the SL (switched live) it should have a brown sleeve on it to show it's being used as a live wire and not a neutral.

The the Heat link then needs a 230V supply to power it connecting to N, L & E This should come via the same 3A fused connection unit that powers the boiler, so that when it's switched off the whole heating system including the Nest Heat link is isolated together.

 

[ericmark]

I would remove the pair brown and blue and use 5 core instead between boiler and heat link, then use the original pair in T1 and T2 to supply the Nest thermostat.

In theory no reason not to have an independent supply to the heat link, it does have volt free contracts, but it is bad practice, people expect if they turn off boiler supply it will kill all.

Or return the Nest Gen 3 and get Nest e instead then the two wires you have is all you need.