Using a smart thermostat isn’t just wise for spending less on heating costs. It can also alert you if there’s an issue with your furnace.
The Google Nest is equipped with a function called Furnace Heads Up, which will alert you if it notices a problem with your heating system. You’ll notice the alert on the thermostat, in the app and in your monthly Nest Home report.
One of the most typical problems is: “Nest noticed that your furnace shuts down within 15 minutes of heating.” Here’s why this is happening and how you can correct 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 switches off. This HVAC game of red light, green light prevents your home from being warm 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 need to be replaced more quickly.
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 pick up on power interruptions that take place 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 restrict airflow. Your furnace will then shut off prematurely to prevent overheating. We encourage replacing flat filters every month, and pleated filters every three months. It’s simple to stay on top of replacing your filter by setting up a Filter Reminder on your thermostat.
If you’ve replaced your filter after getting a Furnace Heads Up alert, you can run a test to see if that repairs the problem.
- Push the ring to pull up the Quick View menu, where you’ll select "settings" and then "equipment."
- The thermostat will show the wires linked to it. Choose "continue."
- You’ll see system components shown. Select "test."
- Choose "Furnace Heads Up" and follow the instructions. Your furnace will go through a 15-minute heating test and give you the results when it’s finished.
Google says if the filter is clean or if your furnace didn’t clear the test, something else could be wrong that requires professional help. If this happens, call Teays Valley Service Experts at 304-760-5088 for furnace repair.
Clean or Replace Your Furnace’s Flame Sensor
Having a dirty or bad flame sensor is another top reason why your furnace might short cycle. You can tell if there’s a problem by watching your furnace as it starts up. Here’s what to look for.
- Remove the door from your furnace so you can look at 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 warmer indoor temperature.
- When you turn on the heat, the fan will begin running first. You should hear it turn on.
- The ignitor will start to glow. The ignitor is either on the left or right of the burners, but it depends on the furnace model.
- Once the ignitor is hot enough, the gas will turn on and the burners will light.
- If the flame sensor can’t detect a flame, it’s usually because it’s dirty or faulty. Your furnace will then turn off as a safety precaution. If your furnace is short cycling, you'll notice the flame and fan shutting down after a few seconds.
If you’re wondering how flame sensors could get dirty being bathed in fire constantly, a blend 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 task is best left to an Expert. That's because an HVAC professional like Teays Valley Service Experts will be able to clean it without damaging it or be able to tell you if it needs to be replaced.
Check Your Furnace’s Exhaust Pipe Often
Your high-efficiency furnace exhausts combustion gases outdoors through a PVC pipe. This pipe can get clogged by snow or bird nests, so you’ll want to ensure that it’s always clear. If the pipe gets plugged, it can cause your furnace to overheat. It could also cause carbon monoxide to flow back into your home, creating a potentially fatal situation.
However, modern furnaces have a pressure switch that typically will stop these situations from happening. Households with young children will often find their kids have jammed toy cars, sticks or nuts into the exhaust if it’s in a location that's accessible by tiny hands. Even this little amount is enough to trigger the pressure switch. The irregular flow of air into and out of the system trips 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 indicating the pressure switch was tripped.
An Expert HVAC technician from Teays Valley Service Experts can check the codes for you and determine 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 Teays Valley Service Experts, our Experts have the knowledge 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, contact us at 304-760-5088 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.