Nest High Voltage Installation

A typical low voltage thermostat with multiple small wires in different colors.

Nest high voltage installation.

High voltage thermostats are usually labeled 110 115 120 or 240 vac note. Install the thermostat and heat link. Thermostats are designed to handle either low current or high current. A typical high voltage thermostat with 2 4 black and red wires.

If it reads something like 110 vac 115 vac or 120 vac then you have a high voltage system and the nest won t work. Incompatible wiring and voltage stranded wires stranded wires aren t compatible with the nest thermostat. To get a custom wiring diagram for installation simply follow nest app s thermostat installation instructions. Symptoms caused by wiring issues usually occur when you re first installing your thermostat.

Each system s wiring is different. The nest thermostat should be installed by a professional. 12v power to thermostat call for heat. However some systems that are high voltage use a higher current sometimes as high as 16a or higher for example electric radiators or electric underfloor systems.

The nest thermostat only supports low current systems since they are by far the most common. Spot install nest somewhere new using the included power plug and cord or using the stand for nest learning thermostat sold separately. High voltage wires if your thermostat is labeled 120v or 240v or has thick wires with wire nuts or has l1 and l2 terminal blocks your system is high voltage and isn t compatible with the nest thermostat. The 2018 nest learning thermostat 3rd generation is not only compatible with high voltage systems but it works as your best friend who is an agoraphobe and never leaves the house.

This illustration is only an example. Contact a local pro and have them install a step down transformer to 20 30v. Check your thermostat s wiring. Find the best place to install your nest thermostat.

4 the nest learning thermostat is compatible with almost all central heating systems including. You must get your own custom wiring diagram with our compatibility checker. In some cases it is possible to make a high voltage system nest compatible. Link before the nest thermostat otherwise high voltage current will irreparably damage the nest thermostat 12.