Nest Underfloor Heating
Nest Thermostat can be used for both Electric and Hydronic Wet underfloor heating systems. It is much easier when it is a single zone underfloor heating system as only one Nest Thermostat / Heatlink pair is required.
Nest Underfloor Heating brings intelligence and simplicity to Underfloor Heating systems. When there are multiple zones that use a manifold based system. One Nest Thermostat / Heatlink pair is required per Zone. Also an underfloor heating junction box is still required and is good practice as it allows for changing thermostat systems easily in the future.
Nest Learning Thermostat with Wet/Hydronic Underfloor Heating Diagram
Nest Learning Thermostat with Wet/Hydronic Underfloor Heating
Shown above is a simplified diagram of multiple Nest Thermostats being installed to a wet underfloor heating system.
This does work in practice however it is recommended by Nest that the Heatlinks be placed minimum 30cm apart due to wireless interference. Other well known systems lose their reliability when placed in close proximity.
Nest Learning Thermostat with Electric Underfloor heating
Nest Learning Thermostat with Electric Underfloor heating – Setup
In order for a Nest Heatlink to be installed to an electric underfloor heating system a Contactor or Power relay will be required as the Nest heatlink is capable of a maximum of 3A load through it’s switching terminals. Shown above is a simplified drawing of how a Nest Heatlink can be installed, to switch an electric underfloor heating exceeding 3A.
There is a setting in the pro setup menu in which you can select Electric as the fuel / heat source. Once the Nest has learnt the heat up times, intelligence begins to take effect.
UPDATE: Please note, wetrooms and bathing areas are not suitable for this setup, as the Nest is not suitable for rooms with high humidity. Usually in wet areas a floor probe is required. Nest Thermostat has no facility for an external probe. Additionally some electric underfloor heating manufacturers require additional safeguards such as a floor probe or temperature thermostat that prevents the floor from overheating. As long as you are able to comply with this, there is nothing electrically different about the nest being used in place of a purpose made Electric Underfloor Heating control. You are essentially performing the same function as an electric underfloor heating control.
Advanced Optimisation of Nest with Underfloor Heating
In order to gain the most out of this combination, of Nest Learning Thermostats with ufh (underfloor heating), you must make sure your underfloor heating is well balanced. All circuits must be adjusted so that they distribute heat optimally and the rooms warm up effectively.
There is a setting on the Nest Thermostat called True Radiant. Usually switched on by default this tries to bring the heating or in this case underfloor on a certain time before the target temperature set point. First you need to learn how long your ufh takes to warm up. For example from when you switch it on to how fast is takes to warm up the room. If it takes 1 hour and 30 mins, then it would be a good idea to set 2 hours as the max duration in which your ufh will come on before hand to reach the set temperature. If you leave the default 5 hours, it’s not a problem, except that your heating may come on much earlier than it needs to.
Another top tip, is that if you are able to make your house take a little longer to gradually warm up, then it will give more time for the Nest Thermostat to detect an even temperature throughout the rooms.
Nest Thermostat E with Underfloor Heating
The Nest Thermostat E, the latest in the thermostat line up is a single channel thermostat with built-in stand. This thermostat is a single channel thermostat without the requirement of a switched live and neutral, can be used for underfloor heating purpose. The only drawback would be that it cannot be placed on the wall and hardwired like a standard Nest Thermostat 3rd Generation. The Heatlink E would have to be placed on the wall where existing underfloor thermostats would have been installed. For more info on the Nest Thermostat E, see Nest Thermostat E
Nest Product Articles
If you are looking on more information on specific Nest Thermostats and other Nest products, we have the following articles’ pages that provide feature lists and comparisons for the Nest products.