Nest T3029EX Thermostat Operation Manual

The Nest T3029EX (Learning Thermostat 3rd Gen, EU/UK) is a smart, Wi-Fi enabled thermostat that learns your schedule and preferences to optimize comfort and energy savings. It supports central heating systems including combi boilers, S/Y-plan, and OpenTherm, with hot water control. Requires Heat Link for 230V AC installations. Integrates with Google Nest app for remote control. Below are the key specifications and operation instructions.

1. Key Specifications 2. Operation Instructions 2.1. Initial Setup 2.2. Setting the Clock and Day 2.3. Operating in Non-Programmable Mode 2.4. Operating in Programmable Mode 2.5. Advanced Features 2.6. Troubleshooting 3. Installation Instructions 3.1. Remove Old Thermostat 3.2. Installing New Thermostat 3.3. Battery Location 3.4. Wiring and Configuration

Key Specifications

Type: Smart learning thermostat for central heating and hot water systems
Compatibility:
- Combi/system boilers, heat pumps (heating only), zoned systems, district heating
- On/Off and OpenTherm control
- Heating: 1-3 stages; Cooling: 1-2 stages; Hot water control
- Wi-Fi required for app and updates
Power Source:
- 230 V AC/50 Hz via Heat Link
- Battery: Built-in rechargeable lithium-ion
- Power consumption: Less than 1 kWh/month
Electrical Rating:
- Heat Link relays: 3 A resistive/1 A inductive
- OpenTherm: 42 V DC max
- ErP Class IV (On/Off) / VI (OpenTherm)
Temperature Range: Setpoint: 40°F to 90°F (4° to 32°C); Operating: 32°F to 104°F (0° to 40°C)
Operating Conditions:
- Humidity: Up to 90% RH
- Wireless range: Up to 30 m
Dimensions: Display: 3.3" diameter x 1.06" H; Heat Link: Compact wall-mount
Features:
- Auto-learning schedule
- Wi-Fi/Bluetooth connectivity
- 24-bit color LCD (480x480)
- Sensors: Temperature, humidity, proximity, motion, light
- Energy Star/ErP certified
Thermostat Configuration Options:
- Maximum stages Heat/Cool: 3/2
- Hot water scheduling
- App/voice control (Google Assistant, Alexa)

Operation Instructions

Initial Setup

1. Install Heat Link: Follow Section 3; power on mains.
2. Pair Display: Attach to base; press ring to start.
3. Configure System:

Download Nest app, connect Wi-Fi, select language.
Choose boiler type (combi, S-plan, etc.), run system test.
Set home details; thermostat learns schedule automatically.

Setting the Clock and Day

1. Syncs automatically via Wi-Fi.
2. Manual: Press ring to menu, turn to Settings > Clock, press to select.
3. Adjust time zone, format (12/24-hour), daylight savings.
4. Day of week auto-detected from schedule and location.

Operating in Non-Programmable Mode

1. Select Mode: Press ring toward wall to open menu, turn to Off, Heat, Cool, Eco.
2. Adjust Temperature: Turn outer ring clockwise to increase, counterclockwise to decrease.
3. Hot Water/Fan: Control via app or menu if configured.
4. Manual Override: Turn ring for temporary hold; resumes after period.

Operating in Programmable Mode

1. Factory Schedule: Default energy-saving settings; learns over a week.
2. Custom Schedule:

Press ring to menu > Schedule, or use app: Devices > Thermostat > Schedule.
Set times/temps for heat/hot water periods; copy to days.
Enable Auto-Schedule for optimizations.

3. Temporary Override: Turn ring to adjust.
4. Permanent Hold: Select Hold in menu/app.
5. Disable Programming: Set manual mode in app.

Advanced Features

1. Early-On: Pre-heats to reach setpoint on time.
2. Safety Temperatures: Prevents extremes.
3. Farsight: Shows time/weather when approached.
4. Energy Reports: Usage insights in app.
5. Home/Away Assist: Auto-Eco via sensors/location; hot water boost.

Troubleshooting

No Display: Check mains power, Heat Link wiring; recharge battery.
Offline: Verify Wi-Fi; restart Heat Link/display.
No Heat/Hot Water: Confirm mode, setpoint; check boiler/fuses.
Help Codes: Refer to app; contact support at nest.com/eu/support.

Installation Instructions

Warning: High voltage (230V AC); professional installation required. Turn off mains power at fuse box.

Remove Old Thermostat

Switch off mains power.
Remove old thermostat cover, label wires.
Disconnect wires from boiler controls.

Installing New Thermostat

Heat Link: Mount near boiler/junction box; connect L/N to mains, heating/hot water to 1-3/4-6 or OT1/OT2.
Thermostat Wires: Connect existing thermostat wires to T1/T2 on Heat Link.
Display Base: Mount base on wall (1.2-1.5 m high) or stand; connect T1/T2 wires.
Attach Display: Snap onto base.
Power On: Restore mains, complete app setup.

Battery Location

Built-in rechargeable lithium-ion in display.
Charges via Heat Link; no user replacement.

Wiring and Configuration

Professional wiring; no polarity on T1/T2. Max cable 2 mm².

Terminal	Description
L/N	Mains power (230V AC)
1/2/3	Heating relay (NC/C/NO)
4/5/6	Hot water relay (NC/C/NO)
OT1/OT2	OpenTherm
T1/T2	To display (12V DC)

Caution: Ensure 30 cm clearance around Heat Link; configure system in app.