Nest E24 Error – Troubleshooting Guide

Anyone’s heart would start beating faster if they’d notice an error code on their smart thermostat. Thankfully, in the majority of cases, these codes indicate a minor issue that can be easily fixed.

A Nest E24 error means ‘no power to the Rh wire has been detected’. Such an indication will appear when the heating system or the actual thermostat is not receiving power and when there is a loose wire or a blown fuse.

Nest E24 Error

The error basically means that Nest cannot detect power to the Rh wire.

Make sure that the unit is receiving power and that all the switches are set to ON (someone might have accidentally turned them off). Check the circuit breaker as one of the breakers could have tripped.

A blown fuse or a loose wire might also be to blame. 

Get to the furnace’s mainboard by taking off the panels. Look for a slot-style fuse on the board – if it is blown, you would have to change it.

You should call a professional if the above tips did not help. E24 error indicates an electrical issue, so you might want to leave the rest of the steps to an expert.

Read: Thermostat Wire Color Code

Nest Error E160

This error code means ‘no power to the Y1 wire detected’. The mistake might appear when you try to log into your Nest account or if it has become really cold in your area.

  1. Turn off the power to the unit, wait for a couple of minutes, and then turn the power back on.
  2. If that didn’t help, then locate the USB cord. Make sure that it’s not physically damaged and then plug the cord into a different port; if the device is still charging, leave it there for 5-10 minutes and then reconnect the wire back to the thermostat.
  3. If such a solution didn’t work as well, then you might have to buy a Nest Power Connector – it will connect the damaged wire to the thermostat.

Read: Temperature Thermostat Problems

Nest E4 Error

E4 error code stands for the same issue as E24, so it looks like the system cannot detect the power to the Rh wire.

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To fix the issue, you should check the power to the system and then ensure that the wires are inserted correctly in the thermostat.

Nest N72 Error

The system can detect the Rh wire, but it is not connected to the equipment. In this case, you would have to troubleshoot low power (the wire is receiving power, but it’s less than expected).

Check all the connectors with wires – the button should stay down once you let it go, this means that the wires have been inserted correctly.

If you can’t fix the error, but the system is running normally, then you can continue using the thermostat. Of course, contacting a professional would be the best decision.

Read: Benefits Of A Programmable Thermostat

Nest E2 Error

No power wires have been detected, a Rc or Rh wire is required.

Make sure that the system is getting power and then check all the wires. Every wire should be fully inserted into the connector and should have ¼ inch of exposed wire.

How Do I Fix Google Nest Error?

You would have to troubleshoot different error codes in different ways. However, when it comes to the ones that involve power and wiring, taking care of the following things would generally fix the problem:

Make sure that the system is getting power

Check the breaker box, the switches, and the thermostat. Everything should be ON and working.

Check the wires in the thermostat

Every single wire should be correctly inserted into the connector, should have ¼ inch of exposed wire, and should be properly connected to the system board.

Why Does My Nest Keep Saying No Power?

You’ll see such an error code if the thermostat wiring is incorrect, if the C wire is not connected (some systems require such a wire or a Nest Power Connector), if the HVAC system is turned off (at the breaker, the fuse box, etc.), or if the system is not receiving any power at all.

How Can I Tell If My Nest Is Getting Power?

The Nest thermostat has a cool feature that lets you check the flow of electricity coming through the wiring.

Select ‘device information’, then ‘settings’, and find the ‘battery section’ in the ‘power section’. The device will show you the Vin, Voc, and lin readings.

Voc should be between 29V and 42V.

Vin – between 29V and 42V (if you have the C wire connected).

Lin – between 100mA and 200 mA (if you have the C wire connected).

What Is Rc and Rh on Nest?

In a nutshell, Rc wire is for the cooling system and Rh wire is for the heating system

Does Nest Need Rc and Rh?

Your thermostat would be powered by a transformer, in case it is a device that combines heating and cooling. The main job of the components is to transform the high-voltage altering current into a low-voltage direct current.

Thermostats of this kind should contain both an Rc and an Rh wire. Some systems might require a jumper wire between the two, but that’s not the case with Nest thermostats.

The devices have an internal jumper between the Rc and Rh connectors. So, if you have a separate heating and cooling system, your thermostat will have these two wires.

Read: Why Furnace Not Responding To Thermostat?

How Do I Fix No Power to Rh Wire?

E4, E74, and some other error codes indicate ‘no power to Rh wire’. Usually, you would have to check the thermostat for loose connections and fix them, if necessary.

The error can also be caused by a clogged drain line.

Is a C Wire Needed for Nest?

In some cases, the thermostat will be able to function by using only the system’s heating and cooling wires. However, at times, the device might require a C wire or a Nest Power Connector to make the unit compatible.

Fact: a C wire is there to provide constant power to the thermostat; it does not control the system’s heating and cooling functions.

What Color Is a C Wire?

C wire or the ‘common’ wire is usually blue or black. However, do bear in mind that the labels and colors might vary.

Why Won’t My Nest Thermostat Connect to WIFI?

Resetting the thermostat might solve the issue.

  1. To reset the network settings, pick ‘settings’, ‘reset’, and ‘network’.
  2. To reset the actual thermostat, pick ‘setting’, ‘reset’, and ‘restart’.
  3. Once the thermostat turns on again, try reconnecting the device to your Wi-Fi (pick ‘settings’ and then ‘network’).

If that didn’t help, then you might have to update the Nest thermostat’s software.

Can Nest Thermostat Connect to 5GHz?

The 2nd generation Nest thermostat only supports 2.4GHz Wi-Fi networks.

There are dual-band devices that support both 2.4GHz and 5GHz.

Can’t Connect to Nest Connect?

  1. Make sure that Connect is plugged in.
  2. The Nest Guard has to be online.
  3. Restart Connect (hold the button down for 8 seconds and release it once it becomes blue).
  4. You can try to move Connect to a different spot.
  5. Don’t forget to regularly update your Nest Guard software.

Why Does My Nest Say In 2+ Hours?

Such a message indicates that it will take 2 hours to get your house to the desired temperature.

This usually happens if:

  • The thermostat has only been recently installed and it is still learning
  • You have reset the system not that long ago
  • A software update is taking place
  • The circuit is not completed or not pending

Does Nest Thermostat Need Charging?

Under normal circumstances, Nest thermostats do not need to be charged (they use the wires of your heating and cooling system to charge themselves).

However, if there is a malfunction in the system, you can plug the thermostat into a power source using a Micro-B cable. 

Read: No Power To The Home Temperature Thermostat – Troubleshooting Guide

How Long Is Nest Warranty?

The majority of devices have a standard 1-year warranty, while the 3rd generation thermostat has a 2-year warranty