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Nest Not Cooling To Set Temperature: 7 Causes & Fixes

Nest Not Cooling To Set Temperature

Step back. Relax.

You’ve just mounted your Nest thermostat on the wall.

Time to get a power nap in.

Wait… Something’s wrong. 

“Why isn’t my Nest thermometer cooling?”

Don’t you worry. The reasons might not be as hard as you think.

Read on to find out:

  • Why your Nest thermometer is not cooling.
  • 7 step-by-step fixes to set it to cooling temperature.
  • How to force your Nest thermometer to cool in 2 hours less.
  • Why wiring and software matters when changing its temperature settings.
  • And so much more…

Why is my Nest thermostat not cooling to set temperature?

Your Nest thermostat is not cooling because of not knowing your home’s cooling system. This results in mislabeling and misplacing your wires. Your circuit breaker may be turned off, and your air handler has a broken fuse. It may also be due to wrong temperature schedules or a needed software update.

Nest not cooling to set temperature – 7 causes & fixes

#1: Not identifying your cooling system correctly.

“Does the blue wire go here? And the red wire there?”

A familiar scene in movies. A dangerous one, actually.

You don’t have to play the guessing game.

But maybe you did when you installed your Nest for the first time. You didn’t know much about your cooling system.

So you mislabeled the wires. Then, you placed the wires in the wrong places.

Not taking the time to get to know your home system can cause cooling problems.

Clear your schedule. You’ll be spending some quality time with your cooling system.

Getting to know your system

First, identify what cooling system you have. You will find the cooling system outside your home. Check its label. See if it is an air conditioner or a heat pump.

If there is none, get the brand name and model number. Search it on Google and find its type.

You can also turn on the heating in your house. If the outside system runs, it means it’s a heat pump.

Another tip is to check the list of compatible systems here. Your cooling system must work on at least 24V. Your Nest Thermostat supports systems that run on most fuel types. Such as electricity, natural gas, and oil.

Re-labeling your Nest thermostat wires

You’ve just found out your cooling system’s name. Congrats on making a new friend.

Now, you should re-label your Thermostat’s wiring. Use sticky tape and a pen. You may have a photo or notes of your original set-up for reference. Also, you can check this on your Home or Nest app.

Then, open Google’s Nest Compatibility Checker. Follow the instructions, and enter your wiring information.

It will show you a diagram of the correct wiring setup for your thermostat.

Rewiring your Nest thermostat

Don’t touch the wires just yet! Make sure to turn off your circuit breaker. Safety first.

Carefully remove your Nest’s display screen. Then, reconnect the wires using the guide from Google’s Compatibility Checker.

Are all the wires in place? Now, double-check if they’re all secured.

Put back the Nest display screen. Turn on your circuit breaker and Nest Thermostat. Wait for it to boot. In minutes, your room should be as cool as a cucumber.

Reading recommendation: Nest Thermostat Cycling On and Off: 6 Reasons and Fixes

#2: Flipped circuit breaker

It’s a huuuuge deal-breaker when you can’t even look over your circuit breaker.

That’s what your Nest thermostat says, of course.

The circuit breaker looks like a box with many switches. These switches are called breakers. This box protects you from electrical mishaps. It’s also connected to all the wires in your home. So the power goes through it. And then to any device plugged in.

Trip one of the breakers. And your device may not work. Just like your Nest Thermostat. 

Take a look at your circuit breaker

First time looking for the magic box? It’s usually located in less crowded rooms. Like your garage or basement. Sometimes, it can be outside. It’s usually grey and mounted on the wall. Ask for help when unsure.

Open the cover. Look for flipped breakers in the Off position. If you see any, turn them back on.

Not having enough electricity can throw off your Thermostat’s function. Especially since cooling eats up much power.

#3: Wrong RC and RH wiring

So, you might be thinking: “What are RC and RH? Are these BTS members?”

RH stands for “red heating.” This connection powers the heating of your Nest Thermostat. RC means “red cooling.” This one allows the cooling system to work.

These connections need the R wire, the RC port, and the RH port.

The problem could be from these wires being misplaced.

Put the “red wire” in place

Before rewiring, turn off your Nest Thermostat. Also, cut the power source.

First, remove the Thermostat screen. You will see the main grid. It has different ports with labels. Your Nest Thermostat has an RC and an RH port.

Look for the R wire. It’s red.

Old thermostats have one R wire connected to both RC and RH ports. It is bridged by a piece of metal called a jumper.

But the Nest thermometer usually needs two R wires. These wires must be put in their ports.

If you have two R wires, check if they’re secured. Also, ensure they are in their correct ports.

If you have only one, put it in the RH port. Turn on your circuit breaker, then your Thermostat. Wait for it to cool.

Still didn’t work? Try putting the R wire in the RC port. Repeat the previous steps. This should get the cooling process running.

#4: Broken fuse in the air handler

Now, what else could be handling the air at home? Say hello to your air handler.

The air handler spreads and controls the air around your home. It also gives heating or cooling. This depends on where it’s placed.

Just like the circuit breaker, it looks like a big box. It can be found in the attic, basement, or garage. 

On the outside, your air handler may look a-okay.

But the inside is made up of many fuses. One blown fuse can affect not only circulation. But also temperature.

Search for a damaged fuse

Look for your home’s air handler. Taking off its cover can be difficult. The cover may be secured with many screws. You may do it yourself or ask for help from a pro.

Once it’s off, inspect all the fuses. Watch out for any damaged fuses. It can be either black due to burns. Or the wire inside it has snapped.

Take out the broken fuse. You can replace them yourself or hire an electrician.

Fuses are mostly affordable. Get a fuse from a brand you trust. It wouldn’t also hurt to get a second opinion.

#5: System slowing down

Reset Thermostat Software

What if the problem isn’t in the hardware… and it’s the software all along?

Remember that all devices run on an intricate system.

Sometimes, these systems can get overloaded. Or it just simply needs a quick breather.

A one-minute sprint gets us gasping for air. How about our Nest thermostats? They’re running almost 24/7. Keeping our homes cool and cozy.

Also, tech companies tweak the software all the time. Maybe you’ve missed an update or two.

Either way, your Nest thermostat is struggling to cool. 

Restart the thermostat

First, turn off your thermostat. Wait for at least five minutes. This will give it time to shut down completely. Then, turn it back on. Don’t worry: no information will be lost.

Wait for it to start cooling. Still not working. Move on to the next step.

Update the thermostat

Your Nest thermostat can automatically update. This is possible when it’s connected to Wi-FI.

Sometimes, a manual update is needed.

Check if your thermostat has a pending update. Open your Home or Nest App. Select your Nest thermometer on the home screen. Go to Settings, then Technical Info or Device Information. You’ll see the current version. And if you have to update.

You’ll update it on the thermostat itself.

For the Nest thermostat, go to your home screen. Select Settings. Tap Version, then Update.

For the Nest E and Nest Learning thermostat, go to your home screen. Select Settings. Tap Software, then Update.

You might also like: Why is my Nest sensor not connecting?

Reset the thermostat

This may be your last option if all else fails. Resetting puts your device back to its original settings.

Before doing this, take note of all your preferred settings. This makes it easier to set it up again. You can also go to Settings and select Equipment. Here, you can record your chosen heating types and temperature settings.

Press your thermostat ring. Go to Quick View Menu and select Settings. Turn the ring to Reset and press.

#6: Thermometer placed in a warmer spot

“I’ve tried so hard and got so far. But in the end, it doesn’t even matter.”

This is your Nest thermostat singing. The poor thing’s trying its best to cool your home. But you mounted it near a window facing the sun.

The cooling might’ve worked in the past. But your Thermostat could’ve detected the wall’s temperature, not the whole house’s. The warmer it was, the harder your device worked to cool.

Now, your device may have gotten weaker. Too weak to produce cool air. All because of its placement.

Put it in a spot that’s not too cold or too hot

Remove your thermostat from the wall. This may involve a few screws or unwiring. You can do it yourself or ask for help from a pro.

Choose an area away from:

  • Doors.
  • Air vents.
  • Hallways.
  • Windows.
  • Your kitchen.
  • Direct sunlight.

Place the Nest thermostat in a room where you frequent most. Where you usually are should be the most comfortable areas.

Note: One room may have different temperatures. The space on a tall shelf can be colder than on a short table.

#7: Mistake in temperature schedule

You’ve gone through the list. And nothing seems to work.

It’s not the hardware. Nor the software. What if it was something you pressed?

You might’ve set a temperature schedule. And expected cold air to brush through your hair at 8:30 PM.

But it could be that you wrote the wrong time. Or the wrong temperature.

Fortunately, it’s very easy to check. You can also adjust the temperature schedule.

Check the temperature schedule

You can see your temperature schedule on the Nest itself.

For the Nest thermostat, go to your home screen. Select your thermostat. Tap Settings and Schedule.

For the Nest thermostat E, open the Quick View menu. Go to Settings, and then Schedule.

For the Nest Learning thermostat, open the Quick View Menu. Then, choose Schedule.

Check your chosen time. You might have set it to a warmer temperature.

Don’t fret. Changing this is easy. It also depends on which thermostat you have.

Change the temperature schedule.

For the Nest thermostat, tap the day you want to change. Select the temperature you want. Change the time. Do this by dragging the numbers up or down. Choose Done to save changes.

For the Nest E and Nest Learning thermostat, press down to select the day. Tap Change to adjust. Turn the ring to choose the time and temperature. Tap Done after every change. To save changes, turn the ring all the way to choose Done.

People also ask: 

Why does Nest take 2 hours to cool?

Your Nest thermostat might say, “In 2 Hours.” This means there will be a delay in the cooling process. This happens when there’s a drastic change in settings.

One second, a warm room at 75°F (24°C) seemed fine. Two minutes, you switched it to 55°F (13°C). Remember: the thermostat needs time to adjust.

How do you force Nest to cool?

You can force the Nest to cool by restarting it. You can also check if there are any updates. Follow the directions in the previous steps.

If your device is fairly new, better wait for it to cool. Your device may still be adapting to its environment. Its in-built delay mechanism protects it from damage.

Read next: Why Does My Nest Thermostat Say “Delayed for Two Hours”?