nest A0001 User manual

Installation step by step
Learning Thermostat
Installation Guide

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The Nest Learning Thermostat for the UK and
Ireland should be installed by a professional.
Please visit nest.com/eu/install to schedule your installation. You’ll see a list of approved
Nest Pro installers nearby and find pricing information.
A Nest Pro will:
• Make sure that your heating system is working. Your system needs to be working and
needs to conform to building and safety regulations before a Pro can start working.
• Find the best place to install your Nest Thermostat.
• Install the thermostat and Heat Link.
• Connect your thermostat to Wi-Fi or help you do it yourself.
• Give you a quick product intro and demo.
If you’ve already bought installation, you can schedule it with your reseller. Find out
more at nest.com/eu/retail-install

Installation step by step
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Contents
Compatibility. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
In the box . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Before you start . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Installing the Heat Link . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Installing the thermostat. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
on the wall . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
on the stand. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Wiring diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
ErP class. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
Nest Labs (Europe) Ltd. LimitedWarranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
WARNING: High voltage. The Nest Thermostat should
be installed by a professional.

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The Nest Learning Thermostat
is compatible with almost all
central heating systems, including:
• Combi boilers
• System boilers with hot water control
• Heat pumps (heating only)
• Zoned systems
• District heating with electrical
control valve
Control systems:
• On/Off
• OpenTherm
A Wi-Fi connection is required
to control the Nest Thermostat
with the Nest app and to receive
software updates.
Compatibility

Installation step by step
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Display Base Heat Link
ScrewsTrim plate
In the box

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You may want to install the Nest
Thermostat somewhere new
Many wired thermostats are installed
in rooms that are rarely used, so the
temperature that they sense can be
warmer or cooler than the temperature
that homeowners feel.
If the current thermostat isn’t in a good
location, install the Nest Thermostat
in a new place with the Nest Stand
(sold separately) in a room that’s used
more often.
→ Placement guidelines on page 12.
Where should you install it?
• Place it within 30 metres of the Heat
Link. Closer is generally better. Walls
and large objects between them can
affect their communication range.
• The Nest Thermostat should be in a
room that’s used often so that it can
read the right temperature, can sense
when the home is empty and know
when to automatically turn down
the heating.
• It should have a clear view of the room.
• Wall-mounted thermostats should
be installed on an interior wall.
• Make sure that it’s away from draughts
and heat sources.
• For zoned systems, install the
thermostat in the zone that
it’s controlling.
Before you start

Installation step by step
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Installing the Heat Link
It’s important to install the Heat Link before the
Nest Thermostat. Do not connect the thermostat
directly to your heating system. High voltage current
will irreparably damage the Nest Thermostat.
The Heat Link is necessary, even if there are
low-voltage wires.

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Installing the Heat Link
1. Switch off mains power
You’ll be working with mains voltage,
so protect yourself, the heating system
and the thermostat by turning off the
power before you start.
Fuse box Switch
CAUTION: High voltage wires
or

Installation step by step
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2. Connect to power and the control circuit
Check the heating system’s wiring to determine what
type it is.
Remove the Heat Link cover and connect the L (live)
and N (neutral) terminals on the Heat Link to the L and
N circuit on the boiler or junction box. This will power
the Heat Link.
Connect the heating control circuit to the Heat Link 1
(normally closed/satisfied), 2 (common), 3 (normally
open/call-for-heat) as needed.
If the system has a hot water control circuit, connect it
to 4 (normally closed/satisfied), 5 (common), 6 (normally
open/call-for-heat) as needed.
If you have an OpenTherm boiler, connect its control
circuit to the OT1 and OT2 terminals.
→ See pages 20-25 for detailed wiring diagrams.
INSTALLING THE HEAT LINK

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3. Connect to the thermostat wires
Skip to the next step if you’re installing
the Nest Thermostat on the stand and
are using the USB cable for power.
Take two wires from the wire bundle that
goes to the current thermostat and
attach them to the T1 and T2 terminals
on the Heat Link.
HEATING
Call-for-heat (normally open)
Common
Satisfied (normally closed)
12 V DC power
Earth
OpenTherm (42 V DC max)
HOT WATER
Call-for-heat (normally open)
Common
Satisfied (normally closed)
230 V AC live and neutral
input power
Installing the Heat Link

Installation step by step
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INSTALLING THE HEAT LINK
4. Mount the Heat Link
Use the screws included to mount the Heat Link
near the boiler or junction box. Then put the Heat Link
cover back on.
To help ensure a good wireless connection
to the thermostat:
• Leave at least 30 cm of space on each side.
• Install it within 30 m of the thermostat.
Boiler
Heat Link Thermostat
30 cm
min.
30 m
max.

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On the wall
Choose this installation method if the
current thermostat connects to heating
wires in the wall and doesn’t need to move
to a better place.
Go to page 13 to start.
Using the stand
Choose this installation method if you’re
replacing a wireless thermostat or
if the thermostat needs to be moved
to a better position.
The Nest Stand is sold separately.
Go to nest.com/eu for more information.
Go to page 14 to start.
Existing
thermostat wires
With the stand, you can put your thermostat
on a desk, shelf or other flat surface
to
Heat
Link
Installing the thermostat

Installation step by step
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5. Install the Nest base
Remove the old thermostat if there
is one. You can attach the Nest base
directly to the wall or use the trim plate
included to cover up any marks.
If you’re using the trim plate, snap it
onto the base first, then screw them
to the wall as one piece.
When installed on the wall, the Nest
Thermostat should be 1.2-1.5 m above
the floor.
6. Connect the wires
Connect the wires coming through
the wall to Nest’s T1 and T2 terminals.
It doesn’t matter which wire goes into
which connector.
→ Continue to page 15.
Installing it on the wall
IMPORTANT: Terminate and insulate
all wires according to the regulations
in your country or region.
INSTALLING THE THERMOSTAT

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Installing it on the stand
7. Install the Nest Stand
Attach the thermostat base to the stand
according to the instructions that came
with it. Connect the power cable to the
base and plug it into a wall socket.
Stand-mounted thermostats should be
placed on a table or shelf 0.75–1 m above
the floor and no further than 1 m from
the edge.
IMPORTANT: Make sure that you
install the Heat Link before
you install the Nest Thermostat.
NOTE: The Nest Stand is sold separately
and comes with its own installation
instructions. Go to nest.com/eu/stand
for more information.

Installation step by step
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Finishing installation and setup
8. Attach the display
Press the thermostat display onto the base until
it clicks into place. Switch on mains power and
the Nest Thermostat will begin setup.
or
INSTALLING THE THERMOSTAT

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10. Control it with the Nest app
To control your thermostat with your
mobile, download the free Nest app
from Google Play or the iTunes App Store.
Then create a free Nest account with
the app.
You can go to home.nest.com if you’re
using a computer.
If you need help, please visit
nest.com/eu/pairing
9. Setup
The Nest Thermostat will turn on and
take you through setup. You can select
a language, connect it to Wi-Fi, and tell
it some things about your home and
system so that it can help save energy.
The Nest Thermostat doesn’t have
a touch screen. Turn the thermostat
display and press it to select.
Finishing installation and setup

Installation step by step
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Getting started
Using your thermostat
Your thermostat can automatically start learning your
schedule or you can choose a schedule with preset
times and temperatures. You can edit your schedule
at any time.
For help with getting started, learning about
Nest Thermostat features, energy-saving tips and
more, please go to nest.com/eu/thermostatbasics
INSTALLING THE THERMOSTAT

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Wiring diagrams
The following diagrams show you how to install
the Nest Thermostat on:
230 V combi boilers (page 20)
Low voltage/dry contact combi boilers (page 21)
S-plan (page 22)
Y-plan (page 23)
OpenTherm boiler (page 24)
District heating with
electrical control valve
(page 25)

General specs
Terminal Specification Notes
L230 V AC/50 Hz mains voltage Live wire
N230 V AC/50 Hz mains voltage Neutral wire
1Heating relay normally closed/satisfied 3 A resistive, 1 A inductive
2Heating relay common 3 A resistive, 1 A inductive
3Heating relay normally open/call for heat 3 A resistive, 1 A inductive
4Hot water relay normally closed/satisfied 3 A resistive, 1 A inductive
5Hot water relay common 3 A resistive, 1 A inductive
6Hot water relay normally open/call for heat 3 A resistive, 1 A inductive
OT1 OpenTherm wire1 42 V DC max.
OT2 OpenTherm wire 2 42 V DC max.
If using T1 and T2, connect to earth
T1 12 V DC power output to Nest
T2 12 V DC power output to Nest
Note: T1 and T2 have no polarity at the thermostat.
Maximum cable thickness = 2 mm²
AC power adaptor
Input: 100-240 V AC, 50/60 Hz, 0.2 A | Output: 5 V DC, 1.4 A
Heat Link
Wiring specs
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230 V combi boiler
L
N
Boiler 12 V
3 A
230 V AC/50 Hz
N L 1 2 3 4 5 6 OT1 OT2 T1 T2
LN
Input power
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