Do you want to sleep well on winter cold nights? And you notice your furnace not working so what should you do in this situation? Many people feel their furnace fails them when they need it the most. And yes it’s True, It’s the essential device that makes your home comfortable on chilly nights. One of the main reasons behind the not working furnace is the thermostat settings. However, there are some more reasons why your furnace is not working.
Top 24 Common reason may your furnace not working
- Thermostat
- Clogged air filter
- Circuit breaker
- Flame sensor
- Blocked ducts
- Overheating furnace
- Changing filters
- Intermittent pilot igniter
- Bad limit switch
- Cracked heater exchanger
- Lack of maintenance
- Low airflow
- Pilot light needs resetting
- A lack of gas
- Damaged ignition
- Dead blower capacitor
- Dirty gas burners
- Faulty igniter
- Furnace cycling off and on
- Air filters
- Blower motor problems
- Gas line
- Air ducts
- Check furnace flame
Check Your Thermostat to make sure it’s ON
This sounds weird but Yes, double-check your thermostat to make sure it’s set to “heat” and adjusted at least five degrees above the current room temperature. You’d be amazed at how often this simple check could prevent a service call!
Here are some quick thermostat checks you can handle yourself:
Step 1: When your furnace not working check the battery. If your thermostat runs on batteries, make sure to change them at least once a year or as needed. Some thermostats are wired directly to your home’s electrical system, while others rely on batteries. If yours uses batteries, look for a low-battery indicator on the display.
Step 2: Open the thermostat and gently blow out any dust or debris that may have accumulated inside. This can help ensure it’s functioning properly.
Step 3: Verify that the date and time are set correctly on electronic or programmable models. Incorrect settings can cause your system to run on an unintended schedule.
Step 4: Check the breaker. Ensure the breaker for your furnace is on. If it’s tripped, turn it off, check the fuse, and reset it if necessary.
Using these simple steps can save you time and avoid unnecessary service calls.
Furnace is Not Producing Enough Heat – Check and Change Your Clogged Filter
If your furnace isn’t generating enough heat, a clogged air filter might be the culprit. The filter in your furnace traps dust, dirt, and other particles, ensuring that only clean air circulates through your home. Over time, the filter can become clogged, restricting airflow and causing your furnace to work harder while producing less heat. This not only makes your home less comfortable but also increases energy bills and puts unnecessary strain on your furnace. To keep your system running efficiently, check the filter regularly and replace it if it’s dirty. A clean filter allows for proper airflow, ensuring your furnace can effectively heat your home.
Here’s how to check and replace your furnace not working filter:
Turn Off the Furnace: Before you start, make sure to turn off your furnace. You can do this by switching off the power at the thermostat or turning off the circuit breaker that controls the furnace. This ensures your safety while you work.
Locate the Filter: Find the furnace not working filter. It’s usually located inside the blower compartment, which may be behind a panel or door on the side, front, or bottom of the furnace. Some furnaces have a filter in the return air vent.
Remove the Old Filter: When your furnace not working slowly and gently take out the old filter. Take note of how it was positioned because you’ll need to insert the new filter in the same direction. Filters have arrows on the sides indicating the airflow direction, so make sure to match this when installing the new one.
Inspect the Filter: While Checking Furnace not working hold the filter up to the light. If you can’t see much light passing through it, the filter is dirty and needs to be replaced. Even if the filter looks okay, it’s a good idea to replace it if it’s been more than 90 days since the last change.
Get the Right Replacement Filter: when your furnace not working check the size of your old filter, which should be printed on the edge. Buy a new filter that matches these dimensions. You can find furnace filters at hardware stores or online.
Install the New Filter: Slide the new filter into the slot, ensuring that the airflow arrows point in the correct direction, toward the furnace. This allows air to flow properly through the system.
Turn the Furnace Back On: Once the new filter is in place, close any panels or doors you opened and turn the power back on. Your furnace should now operate more efficiently, providing better heat.
Set a Reminder: To keep your furnace running smoothly, mark your calendar to check the filter regularly. Depending on usage and filter type, most filters should be changed every 1-3 months.
The furnace is Not Producing Heat – Try to Reset the Home Circuit Breaker
If your furnace isn’t producing heat, resetting the home circuit breaker is a simple yet effective troubleshooting step. Here’s how to do it:
Locate the Circuit Breaker Panel: The circuit breaker panel is typically found in the basement, garage, or utility room. It’s a metal box with a door that houses the circuit breakers for various parts of your home.
Identify the Furnace Breaker: Inside the panel of furnace not working , you’ll see a series of switches or breakers. Look for the one labeled for your furnace. It’s usually marked as “Furnace,” “Heat,” or “HVAC.”
Turn Off the Breaker: Flip the furnace breaker to the “Off” position. This will disconnect power to the furnace. Wait for 30 seconds to 1 minute before turning it back on. This brief pause can help reset the system.
Turn On the Breaker: Flip the breaker back to the “On” position. You should hear a click, indicating the breaker has been reset and power has been restored to the furnace.
Check the Furnace: After resetting the breaker, wait a few minutes to see if the furnace starts producing heat. You may need to adjust your thermostat to ensure it’s set to a temperature higher than the current room temperature.
If Problems Persist: If the furnace not working and still doesn’t produce heat after resetting the breaker, there may be another issue at play. Common problems could include a faulty thermostat, a clogged filter, or a more complex mechanical issue. In these cases, contacting a professional HVAC technician for a detailed inspection and repair is recommended.
Resetting the circuit breaker can resolve issues caused by temporary electrical glitches or overloads, helping restore your furnace’s functionality quickly and efficiently.
Flame Sensor Needs Cleaning
A dirty flame sensor can prevent your furnace not working from operating properly. This component detects the presence of a flame and ensures that the furnace stays on while it’s heating your home. If it gets dirty or covered in residue, it may not work correctly, causing the furnace to shut off unexpectedly. Cleaning the flame sensor is a straightforward process that can improve your furnace’s performance. Here’s how to clean it:
Turn Off the Power: Start by turning off the power to your furnace. This can be done by switching off the furnace’s power at the thermostat or by turning off the circuit breaker that controls the furnace. Ensuring that the power is off will prevent any accidents while you work.
Locate the Flame Sensor: The flame sensor is generally situated next to the burner assembly inside the furnace. It’s a thin, metal rod that sticks out and is often mounted on a bracket. Consult your furnace’s manual if you have difficulty finding it.
Remove the Flame Sensor: Carefully detach the flame sensor from its mounting bracket. This usually involves unscrewing a small screw or bolt that holds it in place. Gently pull the sensor out of its position, taking care not to damage any surrounding components.
Clean the Flame Sensor: Use a soft cloth or fine-grit sandpaper to gently clean the metal rod of the flame sensor. Be cautious not to scratch or damage the rod. If you’re using sandpaper, lightly rub the rod to remove any built-up residue or corrosion. Avoid using harsh chemicals or abrasive materials that could harm the sensor.
Reinstall the Flame Sensor: Once the sensor is clean, reattach it to its mounting bracket and secure it with the screw or bolt you removed earlier. Make sure it’s positioned correctly and firmly in place.
Turn the Power Back On: While checking the furnace not working restore power to the furnace by turning the circuit breaker back on or switching the thermostat back to the “On” position.
Test the Furnace: Set your thermostat to a higher temperature to start the heating cycle. Check to see if the furnace runs smoothly and heats your home properly.
Regular maintenance, including cleaning the flame sensor, helps ensure that your furnace operates efficiently and safely.
Look for Blocked or Leaky Ducts
Explanation: Blocked or leaky ducts can lead to uneven heating, reduced airflow, and decreased efficiency. This can cause some rooms to be colder than others or put additional strain on your furnace.
How to Check: While Checking furnace not working inspect your ductwork for visible blockages or leaks. You can also use smoke or an incense stick to identify air leaks by watching how the smoke behaves near duct joints and seams.
Over Heating or Rapid Cycling Problems
Explanation: An overheating furnace may shut down frequently to protect itself, causing rapid cycling. This issue can be due to restricted airflow, a dirty filter, or a malfunctioning component.
How to Check: Check if the furnace is turning on and off quickly without reaching the desired temperature. Inspect filters and airflow paths, and consider calling a technician if the issue persists.
Changing filters
Explanation: Regularly changing your furnace filters is crucial for maintaining good air quality and ensuring your furnace runs efficiently. Clogged filters restrict airflow, leading to overheating and potential damage.
How to Change: Locate your furnace not working filter, typically found near the intake/outflow duct. Remove the old filter and replace it with a new one, making sure it’s correctly aligned and properly seated.
Check Your Electric Ignition or Pilot Control
Explanation: A malfunctioning electric ignition or pilot control can prevent your furnace from igniting, leaving your home without heat. This could be due to dirt, faulty components, or sensor issues.
How to Check: Inspect the ignition or pilot light area for dirt or debris. If the pilot light won’t stay lit or the electronic igniter doesn’t activate, it may need cleaning or replacement.
Check Your Bad Limit Switch
Explanation: The limit switch prevents the furnace from overheating. A bad limit switch can cause the furnace to shut off prematurely or fail to turn on at all, potentially leading to overheating or no heat.
How to Check: If your furnace turns off too quickly or won’t start, it could be due to a faulty limit switch. Testing or replacing the limit switch should be performed by a professional.
Cracked heater exchanger
Explanation: A cracked heat exchanger is a serious issue that can lead to carbon monoxide leaks. This problem requires immediate attention to avoid health risks.
How to Check: Signs of a cracked heat exchanger include soot buildup, a strong smell, or visible cracks. If you suspect a crack, turn off your furnace and contact a professional immediately.
Lack of maintenance
Explanation: Regular maintenance is essential for keeping your furnace running efficiently and safely. Neglecting maintenance can lead to breakdowns, reduced efficiency, and safety hazards.
How to Perform Maintenance: Schedule annual inspections and tune-ups with a qualified technician. Regularly check and replace filters, and ensure all parts are clean and functioning correctly.
There Is Something Restricting Air Flow
Explanation: Restricted airflow can cause the furnace to overheat, cycle on and off frequently, or fail to heat your home properly. This could be due to dirty filters, blocked vents, or duct issues.
How to Check: Ensure all vents are open and unobstructed. Replace dirty filters and inspect ducts for blockages or leaks.
You Have a Faulty Ignition Sensor
Explanation: A faulty ignition sensor can prevent the furnace from igniting, leaving you without heat. This sensor ensures the burner flames are detected before allowing gas to flow.
How to Check: If the pilot light goes out frequently, the ignition sensor may be dirty or defective. Resetting or cleaning the sensor might help, but replacement could be necessary.
Gas Furnace Blower Runs Continuously
Explanation: If the blower runs continuously, it could be due to a lack of gas supply or a problem with the thermostat or limit switch. This issue can cause the furnace to blow cold air.
How to Check: while checking the furnace not working check your gas supply and ensure the thermostat is set correctly. If the blower continues to run, it might be a limit switch issue, requiring professional inspection.
Damaged ignition
Explanation: A damaged ignition system can prevent the furnace from starting, leaving your home cold. This could be due to wear and tear or electrical issues.
How to Check: Inspect the ignition system for visible damage. If the furnace won’t start, it may need professional repair or replacement.
Dead blower capacitor
Explanation: The blower capacitor helps the blower motor start and run. If it’s dead, the blower won’t operate, resulting in no airflow from the furnace.
How to Check: Listen for a humming noise without the blower running, or test the capacitor with a multimeter. Replacing a dead capacitor should be done by a qualified technician.
Dirty gas burners
Explanation: Dirty gas burners can cause uneven heating, and reduced efficiency, and may prevent the furnace from igniting properly. This is usually due to soot and debris buildup.
How to Clean: while checking the furnace not working turn off the furnace and carefully clean the burners using a soft brush. If you’re uncomfortable doing this, contact a professional.
Faulty igniter
Explanation: A faulty igniter can prevent the furnace from starting, leading to no heat. This is a common issue with older furnaces or those that haven’t been maintained.
How to Check: If the furnace doesn’t ignite, the igniter may need to be tested or replaced. This is typically a job for a professional.
Furnace cycling off and on
Explanation: If your furnace cycles on and off frequently, it could be due to overheating, a dirty filter, or a malfunctioning thermostat. This issue can cause uneven heating and wear out the furnace.
How to Check: Ensure filters are clean and the thermostat is functioning correctly. If the problem persists, further inspection by a technician is advised.
You need to change your Air Filters
Explanation: Air filters trap dust and debris, preventing them from entering the furnace. Over time, they become clogged and restrict airflow, leading to inefficiency and potential overheating.
How to Change: Check the filter’s location in the furnace, remove the old filter, and replace it with a new one. Make sure the new filter is properly seated and oriented.
Blower motor problems
Explanation: The blower motor is responsible for circulating air throughout your home. If it fails, there will be no airflow, leading to no heat or cooling.
How to Check: Listen for unusual noises or a lack of airflow. Testing or replacing a blower motor should be done by a professional.
Inspect Gas Line
Explanation: The gas line supplies fuel to your furnace. Any issues with the gas line, such as leaks or blockages, can prevent the furnace from operating safely or effectively.
How to Check: Regularly inspect the gas line for leaks (you might smell gas) or visible damage. If you suspect a leak, turn off the gas and contact a professional immediately.
Furnace Does Not Blow Air
Explanation: If your furnace isn’t blowing air, the problem might be with the air ducts. Blockages, leaks, or disconnections in the ducts can prevent air from reaching your living space.
How to Check: while checking the furnace not working inspect the ductwork for blockages, leaks, or disconnections. Ensure all vents are open and the blower is functioning.
Look at the Burner Flames
Explanation: The color and shape of the burner flames can indicate the health of your furnace. Healthy flames should be blue and steady; yellow or flickering flames may signal a problem.
How to Check: Carefully observe the burner flames when the furnace is running. If the flames are yellow, flickering, or uneven, it may indicate incomplete combustion or dirty burners, requiring professional attention.
Safety Precautions
Ensuring safety while working with your furnace is paramount. Furnaces involve electricity, gas, and potentially hazardous components, so taking proper precautions can prevent accidents and injuries.
Guidelines:
- Turn Off Power: Always turn off the power to your furnace before performing any maintenance or inspections.
- Avoid Gas Leaks: While checking the furnace not working if you smell gas, do not attempt to fix the furnace. Evacuate the area and contact a professional immediately.
- Wear Protective Gear: Use gloves, safety glasses, and a dust mask when handling furnace components to protect yourself from debris, sharp edges, and fumes.
- Work in a Well-Ventilated Area: Ensure proper ventilation when working near your furnace to avoid inhaling harmful fumes.
- Follow Manufacturer’s Instructions: Always refer to your furnace’s user manual for specific safety guidelines and maintenance procedures.
Safety Switch on Furnace Door
The safety switch on the furnace door is a critical component that prevents the furnace from operating when the door is open. This switch ensures that the furnace cannot start while someone is working on it, reducing the risk of injury.
Usage:
- Check Functionality: Regularly test the safety switch to ensure it is functioning properly. The furnace should immediately shut off when the door is opened.
- Never Bypass: Do not attempt to bypass or disable the safety switch. Doing so can create a serious safety hazard.
- Secure the Door: While checking the furnace not working ensure that the furnace door is securely closed and latched before turning the furnace back on.
Keep the Area Around Your Furnace Clean and Unobstructed
Keeping the area around your furnace clear of debris, dust, and any obstructions is essential for safety and efficiency. A clean and unobstructed space ensures proper airflow, reduces fire risk, and allows easy access for maintenance.
Guidelines:
- Clear the Space: Keep at least 3 feet of clearance around your furnace. Remove any flammable materials, such as cardboard, papers, or chemicals, from the vicinity.
- Regular Cleaning: Periodically vacuum around the furnace to remove dust, dirt, and other debris that could accumulate and pose a fire hazard.
- Ensure Accessibility: Make sure the furnace is easily accessible for inspection, maintenance, and emergency shut-off.
Oil the Furnace Blower Once a Year
When your furnace not working then Start Oiling the furnace blower annually is crucial for maintaining its efficiency and prolonging its lifespan. Proper lubrication reduces friction, prevents wear, and ensures smooth operation of the blower motor.
How to Oil:
- Locate the Blower Motor: Turn off the power to the furnace, then locate the blower motor and identify the oil ports (if applicable).
- Use the Right Oil: Apply a few drops of non-detergent motor oil designed for furnace blowers. Avoid over-oiling, as this can attract dust and cause buildup.
- Reassemble: After oiling, reassemble any components you removed and turn the power back on. Run the furnace to ensure the blower operates smoothly.
Check Your Vents
Regularly checking your vents is important for ensuring proper airflow and efficient heating. Blocked or obstructed vents can reduce furnace efficiency, increase energy costs, and cause uneven heating in your home.
How to Check:
- Inspect Vent Openings: Walk around your home and ensure all vents are open and unobstructed by furniture, curtains, or other objects.
- Clean the Vents: Dust and debris can accumulate in vents over time. Use a vacuum or a soft brush to clean the vent covers and remove any blockages inside the ducts.
- Check for Damage: Inspect the vents for signs of damage or disconnection, and repair or replace any broken components to ensure proper airflow.
Flush Out Drain Lines
Flushing out the furnace’s drain lines is an essential maintenance task to prevent clogs and water damage. Over time, dirt, mold, and debris can build up in the drain lines, leading to blockages and potential overflow.
How to Flush:
- Turn Off Power: When the Furnace not working always turn off the power to the furnace before working on the drain lines.
- Locate the Drain Line: Find the drain line, usually near the furnace’s evaporator coil or near the condensate pump.
- Use a Cleaning Solution: Pour a mixture of water and vinegar or a mild bleach solution into the drain line to break down and flush out any buildup.
- Check for Blockages: If water doesn’t flow freely, use a plumber’s snake or a wet/dry vacuum to clear any obstructions.
- Regular Maintenance: Flush the drain lines every few months to prevent future clogs and ensure proper drainage.
Check to Make Sure Power to the Furnace is On
While Checking the furnace not working ensuring the power to your furnace is on is a basic but critical step in troubleshooting when your furnace isn’t working. A furnace without power will not operate, leaving your home without heat.
How to Check:
- Check the Thermostat: Ensure the thermostat is set to the correct mode (heat) and that the temperature is set higher than the current room temperature.
- Inspect the Circuit Breaker: Go to your home’s electrical panel and check if the circuit breaker for the furnace has tripped. If it has, reset it.
- Check the Power Switch: Many furnaces have a power switch located nearby. Make sure this switch is turned on.
- Verify the Pilot Light (for gas furnaces): If applicable, ensure the Pilot Light is lit. If it’s out, follow the manufacturer’s instructions to relight it, or contact a professional if needed.
In conclusion, a furnace may stop working for various reasons, ranging from simple issues like a misadjusted thermostat or clogged air filter to more complex problems such as a faulty ignition sensor, cracked heat exchanger, or damaged blower motor. Regular maintenance, such as checking and changing filters, cleaning components like the flame sensor, and ensuring proper airflow through vents and ducts, is crucial for keeping your furnace running efficiently and safely.