Have you ever walked into your house on a cold winter day, and your furnace won't turn on? It is the worst feeling in the world. It is freezing outside, you are unsure of what to do, and you are thinking about what could have possibly gone wrong now!
Well, don't worry - help is available. Several causes make your furnace malfunction. So, let's dive into why your furnace will not turn on, and more importantly, how to avoid this chilling scenario.
Only an HVAC Pro can accurately diagnose your unique furnace issue. Get your furnace up and running ASAP with a professional furnace repair.
Stay warm, my friends!
Restore Your Comfort ASAP With An HVAC Pro
How Your Furnace Works
First, let's talk about your HVAC system's heating cycle. Understanding how your furnace works is valuable, especially if you want to know what is preventing your furnace from delivering heat.
So let's begin!
Once the indoor temperature drops below the thermostat's set temperature, the thermostat signals the control board inside the furnace to begin the heating process. The combustion process starts as the gas valve opens and the ignition turns on. The fire ignited inside the furnace warms the room temperature air, then the warmed air is redistributed in your home through your air ducts. Finally, the flue gasses from combustion travel through the heat exchanger and exit your home through the flue pipe.
If you have a malfunctioning heating system, it could be due to many causes, and our HVAC experts have seen it all before! Now, let's get into the top reasons that cause a furnace to not startup.
Why Your Furnace Won't Turn On ?
Furnace Won't Turn On Because The Furnace Switch Is OFF
If you have a heating system that will not startup, you should check the furnace power switch. The furnace switch is the power source and is typically located next to the furnace or on its side. It closely resembles a light switch. First, confirm the switch is in the "on" position and see if your furnace starts up then. If the switch is flipped down in the "Off" position, then your furnace will not turn on.
Furnace Switch
If your heating system still does not start up, it might be due to a blown furnace fuse or tripped circuit breaker.
Tripped Circuit Breaker Explains Why Furnace Won't Turn On
Furnace tripped circuit breaker
Without electricity, your furnace is entirely unable to turn. If the circuit breaker controlling your furnace trips, it will need to be reset. Check your breaker box to see if you have a tripped HVAC circuit breaker. If you have a tripped circuit breaker, flip the tab to restore power to your furnace.
Gas Valve Is OFF
Verify that the gas valve shutoff on the furnace's gas line is turned on. Its handle will be parallel with the gas line if it's on. However, if it's perpendicular, the gas is off. If the gas is turned off, rotate the gas valve handle parallel with the gas line and see if the furnace starts working.
Bad Thermostat
Don't forget that your thermostat is critical in maintaining the temperature exactly you want. If something goes wrong with this device, things can get really chilly! You'll also need batteries for when they eventually die out. So make sure to check now and then, or risk being home all winter without heat!
Damaged or Loose Thermostat Wiring
Dirty thermostat wiring
When any thermostat wires are loose or broken, your thermostat is unable to communicate with your furnace. Therefore, if the connection inside your thermostat is disrupted, then chances are your furnace will not work. You can unscrew your thermostat and check that the thermostat wires are securely attached and have no visible damage.
Incorrect Thermostat Settings
When your HVAC malfunctions, then we recommend checking your thermostat's settings. First, check to make sure it's set to heat. Your heating system will not operate if your thermostat is set to "Cool." Therefore check to ensure that your thermostat is set to "Heat" and not "Cool." Another possibility is that the thermostat has been set to "fan only." Make sure your fan thermostat setting is on "Auto."
If your heating system cannot sense that the room has reached the desired temperature, it will not turn on. Check your thermostat to make sure that it's not set too low. You may also want to consider upgrading to a programmable thermostat so that you can have more control over your home comfort.
