How to Fix Nest Thermostat Delayed?

Nest Thermostat Delayed Fix

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Nest thermostat is a highly rated smart thermostat device that is regarded for its extensive functionality and is a popular choice among consumers.

The programmable, electronic Nest thermostat aids in conserving energy and serves as a reliable option for temperature control and tracking energy consumption. It is an effective tool for optimizing the heating and cooling system in businesses and homes.

One common issue that smart thermostat users may encounter is a Nest thermostat delay message, which can impact the effectiveness of the smart thermostat. This post provides a helpful guide on what to do if your Nest thermostat displays a delayed message.

Why does Nest Thermostat say delayed

The delayed message on the Nest thermostat display is a common issue that may have various underlying reasons.

You may have an underpowered thermostat at your hands, or there may be a power supply shortage. In such an instance, fixing the device’s wiring system may help resolve the issue.

As one of the best smart thermostat options in recent times, Nest thermostats are highly energy efficient and rely on very little power. Contrary to the common perception, Nest thermostats do not derive power from main electricity but from rechargeable lithium ion batteries, which get power from the HVAC system.

If an underlying issue hinders the power supply from reaching the thermostat or the heating and cooling functions are used infrequently, the batteries’ power may drain rapidly. If that is the case, the thermostat’s ability to function may be temporarily delayed due to its low power level.

If such a situation occurs, the HVAC system would be rendered inefficient and may turn on or off at arbitrary intervals. This can consequently cause damage to the system with significant financial repercussions. Hence this situation must be avoided or catered to right away.

However, an underpowered thermostat or power shortage is not the only reason behind the Nest thermostat’s delayed message. There can be other factors causing this as well, and in the following sections, we have addressed these factors along with power issues and offered suggestions for resolving the problems. Let’s have a look!

Problem with the wiring circuit

The Nest thermostat depends on the power supply from the HVAC system in your home. If the circuit is incomplete or there is a missing wire between the HVAC system and Nest thermostat, it could be the reason for the Nest thermostat device displaying the delayed message.

To rule out this probability or address the problem, you must first check to ensure the circuit is complete. Open Nest settings and scroll to Equipment. You will see the wires attached; C is for the common wire, RH is for power, Y1 is for the cooling system, and W1 is for the heating system.

If you do not see a C wire in the display, you must attach a common wire and complete the circuit. In a later section, we have provided a helpful guide on how to install a C wire.

Resolve low power issue

Since the Nest thermostat is intended to perform more diverse functions than conventional thermostats, it requires more power to operate. As mentioned earlier, the Nest thermostat relies on a rechargeable battery which, at times, may drain too fast when the device performs smart functions like motion sensors, connecting to the WiFi, etc.

If the Nest thermostat does not receive sufficient power, you may encounter issues such as inconsistent cooling, heating, or fan operations. This is where the C wire comes in.

When is a C wire required?

Nest thermostats usually draw a charge when the cooling or heating system is activated and does not necessarily need a C wire to function. However, at times, the thermostat can not draw sufficient power, resulting in a Nest thermostat delayed message.

It is an inherent problem of such a setup as continuous power is not supplied to the thermostat, and it only flows through when the system is activated as that is when the wires are switched on.

You can check the current voltage of the internal battery via the display. A certain amount of voltage is required to perform specific functions such as software updates, WiFi connectivity, or motion sensors. If there is a drop in the voltage, these functions cannot be performed. It is because the Nest thermostat will preserve the battery in case of low voltage and will also disable the screen.

In such situations, a c wire comes in very handy. It enables the thermostat to receive constant power, providing a continuous path to electricity and enabling it to flow without waiting for the system to be activated.

Pull out your Nest thermostat’s display and check the panel with label C. This is where a blue wire must be installed in case of a power shortage

Install a C wire for the Nest thermostat

If you do not have a common wire currently, you can install one. Here are your options to replace the missing C wire.

To install a C wire, connect both ends to the HVAC and Nest thermostat device. The wiring circuit is most likely plastered in and over the walls; therefore, it makes sense to seek professional help for an accurate job.

It is also recommended to turn off the power supply to the Equipment during the installation process. You can also use a sender and receiver like Fast STAT to wireless connect the c wire as a replacement for the missing wire.

Use a C wire adapter

A C wire adapter is easy to install and test and is an effective way to resolve the problem of underpowered thermostats.

Firstly, remove the front of the Nest thermostat to uncover wiring terminals. You will see two wires connected to it; have one wire connected to the power terminal and the other to the common terminal.

Now insert the adapter plug into a nearby wall socket. It is then connected directly to the Nest thermostat, which should resolve the delayed message.

You can hook the wire along the wall boundary to eliminate the exposed wirework that may compromise the room’s aesthetics.

A C wire adapter has an instructions manual with simple steps to follow easily. Thus, installation and usage of the C wire adapter should not be a problem.

Use a G wire instead

Another option is to use a G wire as a C wire. The G wire is a green wire usually intended to provide autonomous control over blower fans. For this purpose, you will need to remove the wire from the G-terminal in the Nest thermostat and install it like you would a C wire.

You can do this for blower fans or furnaces. This way, you have an economical solution for supplying constant power to the thermostat.

However, the downside is that you will lose independent control of the ventilation fan. When you repurpose the G wire as a C wire, some fan functionality is lost, as you cannot use the appliance in a fan-only mode.

Nest Thermostat device issues for delay message

If insufficient power supply is not the reason why the thermostat is delayed, there may be other reasons for the Nest thermostat delayed message. Continue reading to find out.

The Nest Thermostat was installed recently

Nest thermostat relies on a machine-learning algorithm. It usually takes a while for it to settle in and learn the schedule. For the first few weeks, you need to regulate the thermostat so as to provide the reference data set.

Eventually, the thermostat learns your schedule, the temperature levels you are used to, and at what times. It can also use phone locations and in-built sensors to shift into eco-mode when no one is home.

Thus the newly installed device may not know how long it can take for your home to cool down or heat up, and it will need time to learn your schedule and know your home before it can function according to your requirement.

If you have a newly installed Nest thermostat that shows a delayed message, you must give it some time to adapt and learn according to the reference data set provided by you before it can give accurate estimates for temperature regulation.

The system was rebooted recently

If you rebooted the system recently, all the saved data in the Nest thermostat would be erased, and it will have to learn your home again from scratch.

You may need to wait until the Nest thermostat has learned about your home, and the delay message will eventually disappear.

Check if the firmware needs to be updated

Like any other smart device, the Nest thermostat requires regular software updates to function optimally.

One reason why the Nest thermostat displays a delay message could be that the device is running a software update and cannot function regularly until the update is complete.

Tips for fixing Nest Thermostat Delayed message

Earlier, we established insufficient power supply or a missing C wire as the causes for the Nest thermostat delayed message. Besides adding a C wire, here are some ways to fix the Nest thermostat delay.

Charge the Nest Thermostat’s Battery

If the Nest thermostat’s battery does not have adequate power, the HVAC system will not have enough incoming power. In this case, you must manually change the thermostat battery to get the device in working order.

To charge the battery, remove the thermostat device’s front to uncover the USB port. Insert a compatible charger into the device’s port and give the battery some time to charge,

Once done, put the front of the device back in its place, and if the drained battery were an issue, the delay notification would disappear after charging.

However, while charging the battery can help fix the issue quickly, it is not a permanent solution. If the HVAC system does not get enough power, you must recharge the battery frequently.

Wait for the recently installed device to learn

If your newly installed thermostat device displays a delayed for 2 hours or a similar message, it should not be a cause for concern. The delay is only because the device has lost its saved reference data and has become like a new device that will eventually learn how your home thermostat is supposed to function.

Give the Nest thermostat some time to settle in, and soon you will have a normally functioning device. You may also see the delay notification if you recently reset the thermostat. In this case, too, you must give the device a few days to adapt.

Check if the firmware needs to be updated

If the Nest thermostat is running a software update, it is unable to function regularly until the update is complete. In this case, you can wait a while and give the device time to complete its updates, after which it will be ready to work normally.


Why does the Nest thermostat say delayed for two hours?

If the Nest device is underpowered or not getting a constant flow of power, or is running an update, or was recently installed, it may display the delayed for two hours message.

How can I resolve the speed issue in the Nest thermostat?

You can resolve the delay issue by connecting a C wire to ensure a constant flow of power to the device and resolve the power shortage issue, which can be the cause of the delay.

Can I manually control the Nest thermostat?

Yes, you can manually adjust the Nest thermostat’s temperature via the touch bar on the device’s right side. Swipe down to decrease the temperature and up to increase it. Once done, tap to confirm, following which the display will show how long it takes until the room reaches the desired thermostat level.


As the article suggests, there are multiple reasons for the Nest thermostat displaying delayed message, and there are various solutions to resolve the issue.

Considering the nature of the issue, you must employ a relevant solution. For instance, if the lack of a constant power supply is the problem, you can install a C wire to resolve the issue. Similarly, if installing the smart thermostat or system reboot is the issue, you only need to give the device some time until it adjusts.

Hopefully, this article provides the guidance you need to resolve the Nest thermostat device issue. If you need further assistance, you can contact Google Nest support.

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