Nest with room thermostat

[Ben3003]

Hi All,
New here so thanks in advance for any assistance. Once I get this resolved happy to share will all a picture and diagram to help others.

I have recently purchased a 3rd gen nest to replace my timer and hopefully room thermostat. I have everything working well thanks to some very useful posts on this site but now I am moving onto the room thermostat replacement and am getting stuck.

Here is what i currently have:

IMG_1844

• Ben3003
• 25 Jun 2017

The problem that I have is how do I replace the room thermo with the nest thermo? I understand that the T1 and T2 should be used to power it up but what do I do about my 3-3 connection? Should I just remove it? Here is the diagram on the current thermo...

Anyone with any ideas? At the moment I have it all working providing the thermo is constantly set to always on, not ideal!
Thanks
Ben

 

[flameport]

Here is what i currently have:

That cannot be all of the wiring - where is the connection to the rest of the system for heating on?
As shown, when the thermostat is on, it just connects L and 3 together.

 

[Ben3003]

That's it! I only have a heating on and a common for heating. So if I jumper the 3 to live it could work? Is that what you are saying? Thanks, Ben

 

[AGAS]

hello ben , the suited and booted man what do you do for a living as you look familiar , just interested thats all

 

[flameport]

I only have a heating on

which is connected where? Your diagram just shows the heating on terminal (3) connected directly to a thermostat and nothing else.

 

[D_Hailsham]

Have you actually read the Installation Manual? If so, which bit don't you understand?

 

[Pauli11]

Ben,
Is it an S Plan or Y Plan connection you are doing (or other)?
In either event, first thing to do is connect two cables between T1 and T2 on the heatlink and the Nest stat. (any way round , it doesn't matter). I would suggest using the L and N cable from your diagram. Connect to the Nest at your thermostat connection using the 2 screwed connection points. At the Heatlink, just move L and N over to the T1 and T2 terminals. That will provide 12v to the Nest stat.

The 3rd cable at the nest side can be taped up or terminated as you won't need it there. Then connect "3" at the heatlink to either the white wire on your Zone valve (for Y Plan connection) or the BW wire on your heating valve (for S Plan connection).

If you are unsure whether you need to do an S Plan or Y Plan connection, have a look at your valves at the tank. If you only have one running to the junction box, it is a zone valve shared between heating and hot water (Y Plan), if you have 2 or more valves (i.e. one for hot water, one for heating and possibly even 2 or more for heating) then it is an S Plan connection you do.

Be careful, once all wired double check the nest connection to T1 and T2 as it only takes 12v to power the nest. If you power it to L and N you will destroy it.

 

[dreadnoughtheating]

going a little off-topic, here but,

If I could really really be bothered, I would count how many queries there are from punters who think they want/need control their heating from the convenience of a smart phone/ipad/whatever.....

nobody but nobody ever requests internet capable controls when I am quoting for an upgrade. Maybe they are just too wise to spend more than they need to when upgrading, realising that like 3d TV, robot lawn-mowers (electric windows in cars even), whatever, that this is just a sales gimmick, with little daily use or real cost benefit to the end user.

Even iffy landlords who 'need' to control the heating find they need someone in the HMO who can reset it when needed, I will make one exception though, holiday let landlords who believe a warm doorstep waft of warmth is a good marketing ploy.

Over & out

 

[Pauli11]

I disagree. I have 2 different reasons to use the Nest systems I own.

One is in a holiday home. I do not have to leave heating on or even set low when I am not in the house. I can monitor the temperature and switch heating on and off accordingly. I can boost it in very cold weather and tun it down again and I don't have to do anything more than lift my Iphone. This will save me a right bit of money. Also, up to now, going up to the house over the winter has meant braving a freezing house for most of the first evening, while the place warms up. Either that, or have the heating on higher for weeks or even months over winter with no-one in the house, wasting oil.
Nest has been a Godsend and works beautifully.

In my home, I have 2 nests for a 3 zone system. Like most teenage daughters, mine hibernates in her bedroom when home. She now has the app and can control the temperature in the bedrooms herself. I like it because I won't be having to play around with an archaic old programmer, with a screen I can hardly see, little buttons an elf would have trouble using, and only 2 on/off combos per zone. Having it all on the phone is far easier, more intuitive, infinitely more informative and a huge leap over what I have left behind.

I haven't yet had either homes hooked up long enough to see how the learning bit works, but Im looking forward to trying it over winter.
All in all, I am delighted so far. This is the future and it will get better. Would I go back to the old plastic programmer and crappy stats? No chance.
How many people would buy a car these days without electric windows? Not many I would suspect. In fact, a huge percentage would not buy a new car without Aircon. Who would have thought that 15 years ago! Sales gimmicks? Not sure your on the right path with that at all.

You are quoting your own experience as a fitter (i presume). But look at the stratospheric rise and no doubt sales of Nest products, and indeed Hive etc, and I would suggest you are way off the mark in underestimating what people want these days. The "Internet of things" is upon us, in 5 years time products like Nest will be commonplace, as we move inexorably to the connected home and the connected lifestyle. Sure as night follows day, its coming. The public want everything to communicate with everything else. This is the world that is now the norm for anyone under 30. They want tech to do the job efficiently and with flair, and that is why it will continue to flourish.

In fact, I have an Amazon Echo Dot on order, and this will allow me to control the heating without even having to reach for the phone, and it will control all of my A/V equipment by voice as well. Technically, reaching for my phone to turn the temp up is now already old hat!

Embrace the future!

 

[Ben3003]

Thanks for the responses everyone. Paul, I will go and check the Y or S settings tonight and see if I can see any of those colour wires. Totally understand the 12v connection to the Nest stat but for the moment I am connecting via USB to rule that out. Once I have it all working then I will connect it up to T1 and T2 over 12v.