Having a smart thermostat isn’t just smart for spending less on heating costs. It can also alert you if there’s an issue with your furnace.
The Google Nest has a feature called Furnace Heads Up, which will let you know if it notices an issue 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 common issues 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 turns on for a short period of time then turns off. This HVAC game of red light, green light prevents your home from heating up and can drive up your energy bill. It can also increase deterioration on your furnace. It may also be more likely to break down and may even need to be replaced sooner.
Without Furnace Heads Up, you might not detect your furnace is turning on and off frequently, since its blower fan might keep running. This feature can detect power interruptions that take place during short cycling.
How Do I Keep My Furnace from Short Cycling?
There are a few simple ways you can prevent your furnace from short cycling.
Replace Your Air Filter Regularly
If your air filter is too dirty, it will restrict airflow. Your furnace will then shut down prematurely to avoid overheating. We recommend changing flat filters once a month, and pleated filters every three months. It’s simple to stay on top of changing your filter by adding a Filter Reminder on your thermostat.
If you’ve replaced your filter after receiving a Furnace Heads Up alert, you can do a test to see if that fixes the problem.
- Press the ring to bring up the Quick View menu, where you’ll select "settings" and then "equipment."
- The thermostat will display the wires linked to it. Select "continue."
- You’ll see system components shown. Hit "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 done.
Google says if the filter is clean or if your furnace didn’t pass the test, something else could be awry that requires professional assistance. If this happens, call McKinley Heating Service Experts at 780-800-7092 for furnace repair.
Clean or Replace Your Furnace’s Flame Sensor
Having a dirty or bad flame sensor is another top explanation why your furnace is short cycling. You can tell if there’s a problem by paying attention to your furnace as it starts up. Here’s what to check 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.
- Switch on the furnace by setting the thermostat to a higher indoor temperature.
- When you switch on the heat, the fan will begin running first. You should hear it turn on.
- The ignitor will begin 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 warm enough, the gas will turn on and the burners will ignite.
- If the flame sensor can’t sense a flame, it’s usually due to the fact it’s dirty or defective. Your furnace will then shut off as a safety precaution. If your furnace is short cycling, you'll notice the flame and fan shutting off after a couple of seconds.
If you’re wondering 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 issue. This job is best left to an Expert. That's due to the fact an HVAC professional like McKinley Heating Service Experts will be able to clean it without breaking it or be able to tell you if you need a new one.
Check Your Furnace’s Exhaust Pipe Frequently
Your high-efficiency furnace exhausts combustion gases outdoors 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 clogged, it can result in your furnace overheating. It could also result in carbon monoxide flowing back into your home, creating a potentially deadly situation.
However, modern furnaces are equipped with a pressure switch that generally will prevent these situations from happening. Families with small children will often find their kids have jammed toy cars, sticks or nuts into the exhaust if it’s in an area that's accessible by little hands. Even this small amount is enough to trip the pressure switch. The irregular flow of air into and out of the system triggers the pressure switch, which shuts down the burners. If this is the underlying cause of your problem, you will encounter short cycling and a furnace error code specifying the pressure switch was tripped.
An Expert HVAC technician from McKinley Heating Service Experts can check the codes for you and determine the problem. Unfortunately, Nest has not evolved to the point where it can interpret the error codes furnace manufacturers produce, so you will still need a pro to help you out.
Let the Experts Solve Your Short Cycling Furnace
If you receive the message, “Nest noticed that your furnace shuts down within 15 minutes of heating,” you know what to do. At McKinley Heating Service Experts, our Experts have the knowledge to resolve any furnace problem quickly and affordably. What’s even better is that we stand behind our repairs with a 100% Satisfaction Guarantee for one year.* To request your appointment, contact us at 780-800-7092 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.