Smart Thermostat Installation
Systems Overview
| System | Notes |
|---|---|
| Hive Active Heating | Requires a Hive Hub connected to the router; wireless receiver at the boiler; smart thermostat replaces existing thermostat |
| Google Nest Learning Thermostat / Nest E | Wi-Fi thermostat; no hub required; Heat Link at the boiler connects to the boiler controls |
| Honeywell Home T6R / T9 | Simple wireless thermostat; Wi-Fi direct; no hub required; T9 adds room sensors |
Wilsons' most common install: Hive Active Heating — straightforward to install, good app, widely recognised by customers.
Qualifications and Scope
Installing a smart thermostat involves mains-voltage wiring at the boiler's heating controls. A qualified electrician should carry out the boiler control wiring. Do not work on the gas system — only the electrical controls.
How a Heating Control System Works
Conventional system: Room thermostat → signals boiler when heating is required → boiler fires. Programmer sets on/off times.
Smart thermostat replacement: The smart thermostat replaces the room thermostat (and often the programmer functionality). In wireless systems, the thermostat communicates wirelessly to a receiver wired at the boiler — replacing the existing programmer or thermostat wiring at the boiler.
Hive Active Heating — Installation
System components
- Hive Hub: Ethernet-connected to the customer's router
- Hive Receiver: Wired at the boiler — receives wireless signals from the thermostat and switches the boiler's heating/hot water demand
- Hive Thermostat: Wireless, battery-powered — placed in the main living area
Step 1 — Install the Hive Hub
Connect the Hive Hub to the customer's router via ethernet and plug in the power supply.
Step 2 — Replace the existing boiler programmer/receiver
Isolate the boiler and heating controls at the consumer unit.
The Hive Receiver replaces the existing programmer or wired thermostat at the boiler:
| Terminal | Connection |
|---|---|
| L | Live (mains 230V) |
| N | Neutral |
| E | Earth |
| 1 (CH) | Central heating demand to boiler |
| 2 (HW) | Hot water demand (if separate hot water circuit) |
Refer to Hive's wiring guides for common UK system configurations (Y-plan, S-plan, combination boiler).
Step 3 — Configure via the Hive app
- Download the Hive app and create an account for the customer
- Add the Hub, Receiver, and Thermostat to the account via the app setup wizard
- Set the heating schedule
- Test: set the thermostat above room temperature and confirm the boiler fires
Google Nest — Installation
The Nest system uses a Heat Link wired at the boiler (similar to Hive's Receiver). The Nest Thermostat connects wirelessly to the Heat Link and via Wi-Fi to the Nest app.
Installation steps:
- Safe isolate the boiler and heating controls
- Wire the Nest Heat Link at the boiler programmer position (L, N, E, CH demand, HW demand)
- Mount the Nest Thermostat on the wall plate
- Power on the Heat Link
- Follow the Nest app setup wizard to connect the thermostat to the customer's Wi-Fi and Nest account
Honeywell Home T6R — Installation
The T6R is a wireless room thermostat communicating to a receiver wired at the boiler.
Installation steps:
- Safe isolate
- Wire the T6R Receiver at the boiler programmer/thermostat position
- Set the DIP switch address on both the thermostat and receiver to the same channel
- Power on and pair the thermostat to the receiver
- Configure the schedule and temperature settings via the thermostat menu or app
Combination Boilers
On combi boilers there is only one zone (no separate hot water cylinder). Connect the CH output only:
- Connect L, N, E to the receiver
- Connect the CH output to the boiler's room thermostat input (typically labelled RT or TH on the boiler)
- No HW output required
Common Issues
| Problem | Fix |
|---|---|
| Thermostat shows no connection to hub/receiver | Check hub is powered and connected to router; check thermostat is within range; re-pair in the app |
| Boiler not firing when thermostat demands heat | Check CH wiring at receiver; confirm receiver shows heating demand; test by bridging the boiler's RT terminals directly |
| Heating not turning off | Setpoint higher than room temperature; check schedule; check receiver relay is correctly controlling boiler |
| App not connecting remotely | Confirm hub/thermostat is connected to internet; check customer's broadband is working |
| No neutral at programmer position | Check if neutral is available at the boiler — run a neutral wire if needed |