Current boiler diagram and looking to go Nest.

[jmac80]

The Honeywell terminals 1&2 in particular will get a bit crowded but they're usually fairly roomy.

You could link a single flex for L&N from one heatlink to the next if it's easier.

Thanks
Ah yes I was thinking it would get crowded with 7 stuffed into 1 terminal as I was drawing it
I was going to ask could I split L/N/E over 2 terminals with jumpers as there is 3 spare ones?
so live would be 1 and 2 and neutral 3/4 etc.. ? Or as you say I could just link the nest boxes from each other..
How does this now look?

 

[jmac80]

I took away the Nest earths on final design for the zones layout as not needed for Nest?

 

[jackthom]

That looks pretty good to me and that's right the nests don't need an earth connection.

 

[jmac80]

That looks pretty good to me and that's right the nests don't need an earth connection.

Thanks for all your help Jackthom, You have made the impossible (for me) possible.
A true gentleman!
Thanks James

 

[Echo the husky]

I was going to ask could I split L/N/E over 2 terminals with jumpers as there is 3 spare ones?
so live would be 1 and 2 and neutral 3/4 etc.. ? Or as you say I could just link the nest boxes from each other..

Yes you can split it across 2 terminals, I would be doing all the connections in the junction box rather than linking at the nests, the nest terminals are rather small.

 

[jmac80]

Yes you can split it across 2 terminals, I would be doing all the connections in the junction box rather than linking at the nests, the nest terminals are rather small.

Yes sounds like a good plan, So the heat resistant 5 core 0.75mm flex is good for everything above? ie: from the fused switch on the wall, to boiler then out to everything else?

Noticed some other posts on random forums, people saying use 1mm or 1.5mm etc for boiler connections.

Surely .75mm is ok for the feed to the boiler, from what I can see it only uses a couple hundred watts.. maybe it has a big start up current though?

 

[Echo the husky]

The supply should have a 3A fuse, 0.75mm² is ample, anything larger just becomes difficult to fit in the terminals.

 

[jmac80]

The supply should have a 3A fuse, 0.75mm² is ample, anything larger just becomes difficult to fit in the terminals.

Great, thanks for all your help also mate, Truly appreciated!

 

[jmac80]

Yes you can split it across 2 terminals, I would be doing all the connections in the junction box rather than linking at the nests, the nest terminals are rather small.

Here is the final tidied up a little and split over 2 terminals for L&N

 

[jackthom]

Yes that makes much better use of the terminals available.

 

[Echo the husky]

That's a good diagram, much better than many manufacturers efforts!

 

[jmac80]

Hi guys
Ok installed 1 x Nest today, Installed slightly different with just one 4 core going to boiler like original stat.
Done this as can only get 1 cable through the gland into the boiler and had no other grommets etc..
So this is how it is installed:

Seems to be working fine
The only thing is either my old danfoss stat was a few degree out or this one is... used to have the old danfoss one set about 20 but this one needs to be at about 23.5 / 24 to achieve the same comfort level.
The old danfoss stats did feel like it had a bit of play in the wheel before it clicked off/on etc..
Thanks everyone