Solved: Nest Noticed Your Furnace Shuts Down Within 15 Minutes of Heating
Having a smart thermostat isn’t just wise for spending less on heating costs. It can also let you know if there’s a problem with your furnace.
The Google Nest is equipped with a feature called Furnace Heads Up, which will alert you if it senses a problem with your heating system. You’ll see the warning on the thermostat, in the app and in your monthly Nest Home report.
One of the most frequent problems is: “Nest noticed that your furnace shuts down within 15 minutes of heating.” Here’s why this is happening and how you can fix it.
Your Furnace is Short Cycling
When you see the message “Nest noticed that your furnace shuts down within 15 minutes of heating,” that means your furnace is short cycling. Short cycling is when the furnace switches on for a brief period of time then turns off. This HVAC game of red light, green light prevents your home from heating up and can increase your energy bill. It can also increase deterioration on your furnace. It may also be more susceptible to breaking down and may even require replacement sooner.
Without Furnace Heads Up, you might not detect your furnace is turning on and off frequently, because its blower fan might keep going. This feature can recognize power interruptions that occur during short cycling.
How Do I Keep My Furnace from Short Cycling?
There are a few easy ways you can prevent your furnace from short cycling.
Change Your Air Filter Often
If your air filter is too dirty, it will limit airflow. Your furnace will then shut down early to prevent overheating. We recommend replacing flat filters every month, and pleated filters every three months. It’s easy to stay on top of changing your filter by adding a Filter Reminder on your thermostat.
If you’ve changed your filter after receiving a Furnace Heads Up alert, you can do a test to see if that fixes the problem.
- Push the ring to pull up the Quick View menu, where you’ll choose “settings” and then “equipment.”
- The thermostat will display the wires linked to it. Select “continue.”
- You’ll see system components displayed. Hit “test.”
- Select “Furnace Heads Up” and follow the instructions. Your furnace will go through a 15-minute heating check and tell you the results when it’s done.
Google says if the filter is clean or if your furnace didn’t clear the test, something else could be wrong that requires professional assistance. If this happens, call Service Experts Heating & Air Conditioning at 587-404-0790 for furnace repair.
Clean or Replace Your Furnace’s Flame Sensor
Having a dirty or malfunctioning flame sensor is another top reason why your furnace might short cycle. You can determine if there’s a problem by paying attention to your furnace as it starts up. Here’s what to check for.
- Take off the door from your furnace so you can see the burners. If you have a viewport in the furnace door, you may not have to remove the door for this.
- Turn on the furnace by setting the thermostat to a higher indoor temperature.
- When you turn on the heat, the fan will turn on first. You should notice it turn on.
- The ignitor will start to glow. The ignitor is either on the left or right of the burners, but it varies according to the furnace model.
- Once the ignitor is hot enough, the gas will switch on and the burners will light.
- If the flame sensor can’t detect a flame, it’s usually because it’s dirty or defective. Your furnace will then turn off as a safety measure. If your furnace is short cycling, you’ll observe the flame and fan shutting down after a couple of seconds.
If you’re questioning how flame sensors could get dirty being bathed in fire continuously, a combination of moisture and chemicals in the air form a thin coating of carbon on the surface. Cleaning a dirty flame sensor will end the short cycling problem. This job is best left to an Expert. That’s because an HVAC professional like Service Experts Heating & Air Conditioning will be able to clean it without damaging it or be able to tell you if you need a new one.
Check Your Furnace’s Exhaust Pipe Frequently
Your high-efficiency furnace vents combustion gases outside through a PVC pipe. This pipe can get blocked by snow or bird nests, so you’ll want to make sure it’s always clear. If the pipe gets plugged, it can result in your furnace overheating. It could also result in carbon monoxide flowing back into your home, creating a potentially fatal situation.
However, modern furnaces have a pressure switch that typically will prevent these situations from happening. Families with young children will often find their kids have stuffed toy cars, sticks or nuts into the exhaust if it’s in a location that can be reached by tiny hands. Even this small amount is enough to trigger the pressure switch. The uneven flow of air into and out of the system triggers the pressure switch, which shuts down the burners. If this is the root of your problem, you will encounter short cycling and a furnace error code specifying the pressure switch was tripped.
An Expert HVAC technician from Service Experts Heating & Air Conditioning can check the codes for you and diagnose the problem. Unfortunately, Nest has not evolved to the point where it can read the error codes furnace manufacturers produce, so you will still require a pro to assist you.
Let the Experts Solve Your Short Cycling Furnace
If you get the message, “Nest noticed that your furnace shuts down within 15 minutes of heating,” you know what to do. At Service Experts Heating & Air Conditioning, our Experts have the expertise to resolve any furnace problem quickly and affordably. What’s even better is that we back our repairs with a 100% Satisfaction Guarantee for one year.* To book your appointment, call us at 587-404-0790 or schedule online.
*Not applicable to the Advantage Program. See your signed Advantage Program Agreement for full details and exclusions. 100% Satisfaction Guarantee is subject to certain restrictions and limitations as set forth in the applicable Terms and Conditions.