Nest 3rd Gen - will this work.

25 Nov 2016
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United Kingdom
Hi people, 1st post, so be patient please.

I want to install the latest version of the nest and need some tips.

My set up is :- 4 year old Worcester Bosch 30ri straight boiler, a Honeywell digital thermostat and a British Gas UP1 programmer. The hot water is stored in the cylinder upstairs and has a cylinder stat.

So, I'm thinking that the Nest is a glorified programmer/switch. Will I just be able to ditch the the programmer and install the heat link in its place? I'm assuming that the programmer, a bottom of the range jobbie, just supplies the feeds at the set times and nothing else. The Nest is probably going to sit in a stand and therefore I won't be using the T1 & T2 terminals.

As for me, I'm a lift engineer by trade and work on 110, 240 & 415 vac and 600v dc all day so I'm confident to work on electrical equipment.

Comments please most welcome - Rob
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I've had a 100 views and no comments....

Is there no one that can advise me if this is the way to proceed. Please, please and please again.:)
I've just had a Worcester Bosch 30i installed using only a nest and the heat link to control the central heating and the hot water.
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Lower, thanks for your reply.

All of I'm planning to do is replace my existing programmer with the Nest Heat Link. The programmer is very old and only actually controls the turn on/off times (it has 4 functions - OFF, ONCE, TWICE & CONSTENT). I haven't taken the programmer off yet but looking on line, it would seem that it just gives a supply to the CH and HW at the times set. As far as I can see, the Nest Heat Link does exactly the same. Googling the subject just makes things confusing. People are adding, ditching and changing wires in terminal boxes. All my wiring will stay intact, unaltered because the heat link is only preforming the same function as the old programmer. Unless anyone know different......:unsure:
I would post this in the electrics forum, anything wiring related should be there.

A picture would also help a lot
Dear Liftguy, the short answer to your query is YES, the remote relay box (the heat link) will switch mains onto the relevant parts of the heating control wiring. Be aware that the Nest temperature control also contains the room temperature sensor, so must be carefully sited away from sources of heat in use
I'd also add that, when quoting the settings from your old programmer, you pay attention to the detail. A single letter in the wrong place made the word CONSTENT (actually not a word). Imagine the confusion if the same happened elsewhere, and you became a LOFT guy?


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