Shutting off the house seems extreme, but you could easily damage the furnace control board if you let the wrong wires touch during the installation. Most furnaces have a fuse to protect the 24V components, though. Show activity on this post.

Can you install Nest Thermostat without turning off power?

You should always turn off the power before you connect or disconnect any wires from your Google Nest thermostat, and you should test to make sure that the power is off. This helps protect you and your equipment during installation or troubleshooting.

Does Nest Thermostat steal power?





The Nest learning thermostat is a power stealing thermostat which can cause system malfunction or improper system operation. The solution is to add what is known as a common wire, this wire is a separate 24 volt supply dedicated to charging your Nest thermostat.

What should I turn off when installing Nest?

It is necessary to completely turn off the electricity running to your heating and cooling system. When Google states in the instructions to have the power to your heating and cooling system off, this extends beyond simply making sure your air conditioning or heat isn’t running at the time of installation.

Is a thermostat on its own breaker?

You just put off the circuit breaker marked “HVAC,” “Cooling” or “Heating.” All power to the HVAC system will be cut. This means the power of the thermostat will also be turned off automatically. However, you might encounter a problem with the breaker panel if the breakers are not marked.

Does thermostat get power from furnace?

Most room thermostats on heating and cooling systems receive their 24V AC electrical power from a low voltage transformer that itself is usually found at the boiler or furnace (blue arrow in our photo at left).

Is turning off the breaker the same as unplugging?





Thank you. Flipping the breaker just disconnects the power. Unplugging the unit disconnects the power, Neutral and ground. For most repairs it should not make a difference as long as you are sure that the correct breaker is flipped.

How does a power stealing thermostat work?

A typical thermostat uses a 24-V AC system to power the HVAC control system. Power stealing enables smart thermostats to extend the life of the battery backup by stealing power from the 24-V AC line without affecting the HVAC load operation.

Does a Nest Thermostat have a battery?

The Nest Thermostat receives power from your HVAC system. It also uses 2 AAA alkaline batteries as a backup, or to supplement if your system can’t deliver enough power.

What is a current robbing thermostat?

Current robbing means, that it is a digital tstat that doesnt need a common to operate, but must have batteries in order for the relays to operate correctly.

Can you get shocked by thermostat wires?



Virtually all room thermostats operate on low voltage that carries little risk of harmful electric shock. However, it is always wise to shut off power to a thermostat at the service panel before examining or working on it.

How do I turn the power off on my Nest thermostat?

Nest app

  1. On the home screen, select your thermostat.
  2. Choose Mode. . (You may see “Cool,” “Heat” or “Heat • Cool” below this icon.)
  3. Select Off.


Can thermostat wires cause fire?



The safety commission reports that contact between the thermostat wires and household line voltage can damage the thermostat and cause a fire.

Can low voltage wiring cause a fire?

When several things line up and goes wrong, low voltage wiring can cause fires, explosions and shocks under the right conditions. When indoor rated system get soaked with water due to power surge and lightning.

Why would a thermostat smoke?

Cooling System Doesn’t Start Up



Alternatively the thermostat could be affected by an accumulation of dirt, dust, soot, cigarette smoke or cobwebs which can coat the electrical and mechanical components.

Where do thermostat wires go?

Thermostat Wiring Tips



The W wire is connected to your heating system. If your thermostat controls your heat, you will have a white wire. The Y wire is yellow and connects to your air conditioning compressor. The G wire is green and connects to the fan.

What happens if you wire a thermostat wrong?



Potential consequences of improper installation could include: Electric shock. Blowing a circuit breaker. Damaging the thermostat unit, the electrical system or even the AC/furnace unit itself.

Does a nest require AC wire?

With a Nest Thermostat E or Nest Learning Thermostat, you’ll need to install a C wire if the thermostat has power issues or its battery often drains.

How do you wire a Nest thermostat?

Quote from the video:
Quote from Youtube video: Simply hold down the connector button and push the wire all the way.

Can I install Nest thermostat myself?

In most homes, installing a Google Nest thermostat is an easy DIY project that takes about 20-30 min. The Nest app’s step-by-step instructions make it easy to install and wire your thermostat, so use it as your main guide. Refer to this article if you need extra help.

How do I connect my Nest thermostat without C wire?



Quote from the video:
Quote from Youtube video: For the common wire. So what you would do is go to your nest thermostat. Take off the G wire. Usually. It's going to be the green wire going to G. So you press on it you pull it out and before.