HVAC Philly’s 7 Reasons Your Furnace May Not Be Kicking On
The last thing anyone wants on a cold day is for their furnace to fail. When you notice your furnace isn’t kicking on or heating your home, it’s often due to one of a handful of common problems.
The last thing anyone wants on a cold day is for their furnace to fail. When you notice your furnace isn’t kicking on or heating your home, it’s often due to one of a handful of common problems. The good news is, before you call a professional heating repair Philadelphia service for help, there are a few simple things you can check yourself.
Here are seven common reasons your furnace might not be kicking on and what you can do about it.
1. The Thermostat Has Issues
Your thermostat is the command center for your furnace. If it’s not working correctly, the furnace won’t get the message to turn on.
What to do:
- Check the batteries: If you have a digital thermostat, replace the batteries. This is one of the easiest and most common fixes.
- Verify the settings: Ensure the thermostat is set to “Heat” and the temperature is set higher than the current room temperature.
- Inspect for dirt: Gently remove the thermostat cover and clean any dust from the sensors, which can interfere with its ability to read the temperature accurately.
2. Tripped Circuit Breaker or Blown Fuse
Even a gas furnace needs electricity to run. A tripped breaker or blown fuse can cut off power to the system’s vital components, like the blower motor and ignition.
What to do:
- Check your electrical panel: Locate the circuit breaker box and look for the switch labeled “Furnace” or “Air Handler.” If it’s in the “off” or middle position, flip it firmly to the “on” position.
- Don’t ignore repeat trips: If the breaker trips again immediately, you likely have an electrical short and should call an HVAC technician.
3. Clogged Air Filter
A dirty, clogged air filter is the most common reason for furnace failure. Restricted airflow can cause the unit to overheat, triggering a safety shut-off switch to prevent damage.
What to do:
- Inspect the filter:Find your filter—often located where the return duct enters the furnace—and pull it out.
- Replace if dirty:If the filter is dark or completely caked with dust, replace it with a new one. In most homes, filters should be changed every 1 to 3 months.
4. The Pilot Light is Out (Older Furnaces)
For older furnaces that use a standing pilot light, a simple draft or a clog can extinguish the flame. If the pilot light is out, the furnace won’t have a source of ignition for the main burners.
What to do:
- Follow manufacturer instructions:Safely follow the relighting instructions found on your furnace’s access panel or in the owner’s manual.
- Call a professional if it won’t stay lit:If the pilot light won’t stay lit, the thermocouple may be faulty and will need professional service.
5. Faulty Electronic Ignition or Flame Sensor
Newer, high-efficiency furnaces use an electronic ignition system instead of a pilot light. If the igniter is cracked or a flame sensor becomes dirty, the furnace won’t fire up.
What to do:
- Inspect and clean the flame sensor:A dirty flame sensor is a very common problem. With the power off, carefully remove the sensor (a small metal rod) and clean it gently with a fine-grit pad or a clean cloth.
- Call for a faulty igniter:If you hear a series of clicking sounds but no ignition, the igniter itself may be defective and needs to be replaced by a technician.
6. Closed Gas Supply Valve
A furnace that runs on natural gas can’t function without its fuel source. It’s possible the gas valve was accidentally closed during maintenance or another project.
What to do:
- Locate the valve:Find the gas line and valve leading to your furnace. The valve is open if the handle is parallel to the pipe. It’s closed if the handle is perpendicular.
- Test other appliances:If other gas appliances, like your stove, are also not working, the issue may be with your main gas supply and you should contact your utility company.
7. Clogged Condensate Drain (High-Efficiency Furnaces)
High-efficiency, or condensing, furnaces produce moisture that drains away through a small pipe. If this pipe or the condensate pump clogs, a safety switch will trip and shut down the unit.
What to do:
- Check the drain pan:Look for a full drain pan or standing water around the unit.
- Clear the clog:A wet/dry vacuum can be used to clear a clog from the drain line. You can also flush the line with a vinegar and water solution.
STAY WARM MY FRIENDS
