Is your Nest Thermostat Not Cooling at Night? (7 Actionable Steps)

Is your body melting into a sweaty mess every morning because your air conditioner stopped working again?

Perhaps the culprit is your Nest thermostat.

There’s no need to stress; your broken AC can be fixed with no effort on your part.

In the event that your Nest thermostat is not providing overnight cooling, follow these seven steps:

You should change the Nest thermostat’s schedule.

Activate and deactivate the HVAC system.

The Nest thermostat may need to have its wiring checked and perhaps fixed.

Your air conditioner needs to be checked and fixed.

You should inspect the drain pan and drain lines of your air conditioner.

Changing out the battery on an older Nest device.

Remove the energy-saving box by contacting your utility provider.

Keep reading and I’ll explain everything in layman’s terms, so you won’t have to hire an expensive HVAC technician just to figure out your smart thermostat.

Okay, so let’s get going.

Table of Contents  Hide 
1. 1. Reset the Schedule on Your Nest Thermostat
2. 2. Turn Off the Power for the HVAC System and Back On
3. 3. Check and Fix the Wiring in Your Nest Thermostat
4. 4. Check and Repair Your AC
5. 5. Check Your AC Drain Pan and Drain Lines
6. 6. Replace the Battery on an Older Nest Model.
7. 7. Have Your Utility Company Remove the Electricity-Saving Box

1. Reset the Schedule on Your Nest Thermostat

Amazing technology best describes the Nest thermostat.

It can figure out your preferred temperature range based on how you feel and stick to that.

Nonetheless, it’s possible that a fault in Nest caused it to set the wrong temperature for the night.

The easiest thing to attempt if the timetable isn’t working is to reset it. To put it simply:

Launch the thermostat’s configuration menu.

Select your schedule under Reset and apply the necessary actions.

The button to press is Reset (or Clear for other Nest models).

Change your nest’s schedule to better suit the long, hot summer evenings.

2. Turn Off the Power for the HVAC System and Back On

You would think that everything would always function properly with today’s technology.

We still have to resort to the “turn it off and back on” method occasionally, even with the most modern thermostats and air conditioners.

This workaround will resolve the problem regardless of the hardware used.

The first step is to switch off the HVAC system’s power at the breaker box.

The thermostat needs the same treatment.

And then just turn it off and walk away for a while.

Before you assume the air conditioner is completely turned off, check the lights to be sure there is no power left.

A generator should be turned off if present.

To restart the electricity, wait 5–10 minutes.

Change the thermostat as needed and check the next evening to see if the problem is still there.

3. Check and Fix the Wiring in Your Nest Thermostat

One common source of problems is faulty thermostat wiring.

Since it functioned properly all winter long, you might not have noticed the wiring problem until now.

However, improper wiring is typically to blame if the air conditioner isn’t cooperating with the thermostat.

When wires become overheated, they can become ineffective.

A malfunction in the wiring may not always manifest immediately.

It could be effective initially, but the wire will likely become untight and fall out with time.

Most wiring problems stem from missing or improperly connected C wires.

The Nest gets its power from a shared electrical outlet.

This may not be a necessary component of your thermostat, but it can contribute to problems like the one you’re experiencing.

Turning off the power to the HVAC system and the Nest will allow you to fix the problem.

Take the nest away from the wall so that you can study the wiring in detail.

You should unplug any wires that are hanging out of their terminals and reattach them securely.

Focus your attention on the C terminal. Identify the missing common wire and connect it if necessary.

4. Check and Repair Your AC

You may have an issue with your air conditioner if the thermostat isn’t working properly to chill the house.

The average person has no idea how much upkeep is required for an air conditioner.

Every month, you should change the air filter and make sure the fins and fan aren’t caked in dust.

In addition, your air conditioner will not function without sufficient cooling.

Any problems with your air conditioner will be obvious throughout the day, of course.

Check to see if you need to add more coolant to your air conditioner and make sure all of its parts are clean.

5. Check Your AC Drain Pan and Drain Lines

Over time, condensation will cause your air conditioner’s drain pan to fill with water.

To keep leaves and dirt from clogging the drain lines, they need to be flushed every so often.

Your air conditioner won’t work correctly if it gets clogged up because of a full drain pan and blocked drain lines.

At night, as temperatures drop, the trapped water could expand or freeze, making the situation even more difficult.

This could lead you to believe that the Nest thermostat is the problem, despite the fact that the fan continues to operate normally.

How to clean the air conditioner’s drain:

Take off the stopper in the sink drain.

Take a thin wire brush and scrub the inside of the drain.

Combine a bleach-and-water solution and pour it in. Vinegar can be used as a substitute for bleach.

You can turn on the air conditioning while the mixture sits for 15 minutes.

If the drain pan is still full, wait 15 more minutes before turning on the air conditioner.

6. Replace the Battery on an Older Nest Model.

Perhaps the battery in your Nest thermostat has gone bad after years of reliable service.

As I mentioned, this is connected to the widespread wire problem I described before.

The Nest thermostat requires the C wire to function.

The thermostat is useless if it can’t keep the same temperature because the battery is always dead.

It’s a lot more prevalent than you might think.

Still, upgrading to a new Nest isn’t required.

Swapping out the battery is usually all it takes to get your AC working again after dark.

In this video, Cameron Sino demonstrates how to change the battery in an older Nest thermostat:

7. Have Your Utility Company Remove the Electricity-Saving Box

According to Rochelle Ann G., a utility company will put a box in your HVAC system that monitors and adjusts the amount of electricity being used.

That could be the case if your air conditioner is functioning normally during the day but not at night.

The price of electricity drops at night, so that’s when most people choose to use their most energy-hungry gadgets.

Also, if the energy-saving box sees that the HVAC system is using too much energy, it will turn off the power to the system.

The box is typically situated next to the air conditioning or electrical panel. Common features include red and green blinking LEDs.

It is recommended that you get this box removed by a professional technician.

Contact the business that first set up your HVAC system to have them perform it for you.

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