Heat Link is a device that comes with your Google Nest thermostat in Europe. It connects to your heating system in order to start and stop your heating and is controlled by the Nest thermostat.
Each Nest thermostat model comes with a Heat Link designed specifically for that model. Here’s what the different Heat Link models look like:
| Nest Thermostat E | 3rd generation Nest Learning Thermostat | 2nd generation Nest Learning Thermostat |
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How the Nest thermostat and Heat Link work together
With your Nest thermostat and Heat Link, you can heat your home to the temperature you want, when you want. Here’s how the two devices work together:
- Your Nest thermostat lets you set a schedule with specific times and temperatures. You can also turn your thermostat’s dial to select a new temperature any time you like.
- Your thermostat senses the ambient temperature in your home. It can also take other factors into account, such as the current weather and how long your home usually takes to heat up and cool down.
- To keep your home at the temperature you set, your thermostat will automatically turn heating on and off by sending a signal to Heat Link.
Installing Heat Link
Can I install a Nest thermostat without using Heat Link
Can I connect a Nest thermostat directly to my boiler using existing thermostat wires?
No. The thermostat cannot be wired directly to your heating system.
Using Heat Link to control your heating allows you to put the thermostat where you’d like. So if you don’t have thermostat wires in the wall or if the existing thermostat was poorly placed, you can still install your Nest thermostat in a good spot.
Using Heat Link
How is Heat Link different from a programmer?
While Heat Link and a programmer both control your heating system, they aren’t the same.
A programmer is a stand-alone device that turns your heating system on or off. Some programmers include a schedule, but this schedule is not based on the temperatures you want. All it will do is turn the heat off during the times that you’ve selected.
Heat Link lets you heat your home to the temperature you want, when you want. Heat Link replaces either your programmer (if you have a 2nd or 3rd gen Nest Learning Thermostat) or your existing thermostat (if you have a Nest Thermostat E). Working together, Heat Link and your Nest thermostat combine the functionality of a thermostat and a programmer, so you no longer need a programmer.
Can I use Heat Link to turn on the heat, instead of Nest thermostat
Yes, Heat Link includes a button you can press to turn heating on and off manually.
We don’t recommend using Heat Link to manually control heating unless there is a problem, for example, if your Nest thermostat loses its connection with Heat Link.
For more information about manually controlling your system with Heat Link, visit the following article:
Differences between Heat Link models
The basic operation and use of the different versions of Heat Link are nearly identical, but there are some differences.
How to tell which Nest thermostat and Heat Link you have >
The following table shows the differences between Heat Link models. All other features are essentially the same.
| Heat Link for Nest Thermostat E | Heat Link for 3rd gen Nest Learning Thermostat | Heat Link for 2nd gen Nest Learning Thermostat | |
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| Hot water control for a system boiler with separate hot water tank | - | ✔ | - |
| Hot water control for a combi boiler | ✔ | ✔ | - |
| Built-in temperature sensor | ✔ | - | - |
| Compatible with OpenTherm | ✔ | ✔ | - |
| Uses replaceable batteries | ✔ | - | - |
| Number of status lights | 2 | 3 | 1 |
| Connection to Nest thermostat | Wireless | Wireless or wired | Wireless or wired |
| Location | Replaces the existing thermostat on your wall | Near your heating system | Near your heating system |
| Installation | DIY or Nest Pro | Nest Pro | Nest Pro |
Learn how your thermostat communicates with the Heat Link
Your Heat Link and thermostat can communicate wirelessly or via a wired connection, depending on your thermostat model, your system type and how you’ve installed your thermostat.
The Heat Link doesn’t use your Wi-Fi router or network, instead, it uses a wireless mesh network called Thread to directly communicate with your thermostat.
The Thread connection is used to send commands from your thermostat to the Heat Link like changing the temperature and turning hot water on or off. It’s also used for sending software updates to the Heat Link.
In addition, the Heat Link reports the temperature it senses to your thermostat. For instance, your Heat Link in the hallway may sense a slightly lower temperature than your thermostat in your living room. Tap on your thermostat in the app to see the temperatures that your Heat Link and thermostat are currently reporting.
Learn more about Thread networks >
Nest Thermostat E
The Nest Thermostat E exclusively uses a wireless Thread connection to Heat Link. There is no way to directly wire it to the Heat Link.
This is because the thermostat comes with an integrated stand and isn’t designed to be mounted in place of your old thermostat. Instead, the Nest Thermostat E’s Heat Link is mounted where your old thermostat was, and is connected to the thermostat wires.
Nest Learning Thermostat
You have two options for Nest Learning Thermostat installation: placing it on the Nest Stand, or installing it on the wall in place of your old thermostat.
- If you choose to use the Nest Stand, your thermostat will only use the wireless Thread network to communicate with the Heat Link.
- If your Nest thermostat is installed on the wall and connected to your old thermostat’s wires, it will use both the wires and wireless Thread to communicate with the Heat Link.