Finding that your gas furnace won’t ignite is not only inconvenient but also stressful. Handling a non-responsive gas furnace can be daunting, especially if you can’t identify the exact cause of the breakdown. While you should certainly never try to repair your own furnace, it’s a good idea to learn how to troubleshoot your furnace and identify some reasons why it won’t ignite.
1. The Switch Is off or Faulty
A gas furnace has a switch, the heating system’s power source. This is the first thing you should check when the furnace fails to turn on. Ensure the switch is functional and it’s in the ‘on’ position. Since it resembles a light switch, it’s easy to turn it off mistakenly. If your furnace switch can’t flip in the ‘on’ or ‘off’ position, it may be broken and need replacement. The switch can also get dirty and needs cleaning to remove dust or other particles.
2. A Defective Thermostat
A thermostat is vital in maintaining the correct temperatures to warm your home. A defective thermostat can prevent the furnace from turning on to provide much-needed warmth. Check out the thermostat’s settings if the gas furnace is on and can’t generate warm air. You can adjust the temperature settings upwards and see whether the furnace will start working. You must also check if the thermostat’s batteries have died out and replace them regularly.
3. The Gas Valve Is Off
Your furnace needs a continuous gas flow to generate heat for your home’s comfort. If the furnace is on and there is no warm air circulation, check the gas valve and ensure it’s on. You should also ensure minimal to zero interference with your gas supplier before the start of the cold weather. If there is a gas leakage along the gas line, ensure all the holes are perfectly sealed. If the gas valve is broken and can’t turn on, contact a professional to help fix gas issues.
4. Clogged Air Filters
Neglected air filters can make your furnace struggle to generate enough heat. Dust, debris and other particles can get trapped and block air filters. This can eventually obstruct the flow of warm air from your gas furnace. Apart from blocking warm air circulation, the filth can cause the furnace to overheat, resulting in irreversible damage. Inspect and replace the air filters frequently to ensure that warm air reaches all rooms in your home. You can involve our HVAC experts to help you clean or replace them.
5. Disruption of Power Supply
Your gas furnace needs a constant power supply to function effectively. If you have electricity, turn on the furnace but still can’t produce heat, check on the circuit breaker box. If the breaker has tripped and you don’t know how to fix it, you can ask for help from an electrician. Additionally, make sure the gas furnace’s power connection is attached to it correctly. Electrical hitches can be challenging, and you must take safety measures to protect the furnace and your home.
6. The Pilot Light Has Gone Out
Some conventional furnaces have a pilot light and operate on natural gas. This light ignites the gas flowing to the burner to help the furnace generate warm air. Pilot lights can go off for various reasons, causing your furnace to stop producing warm air. If it goes off repeatedly or fails to relight, there might be a more challenging underlying issue. In this case, you’ll need the assistance of HVAC experts.
7. Problems With the Duct System
Air ducts are the channels that supply heat in your home. Your furnace duct system plays a vital role in blowing warm to keep your house warm during the freezing months. You can have a functional heating unit, but poorly installed and clogged ducts can block heat circulation. If the ducts are worn out, holes may also form in them. This will cause the hot air to leak out into the attic.
8. Lack of Regular Maintenance
Your gas furnace plays a significant role in your house. It’s the last piece of equipment you wish to avoid malfunctioning, especially during the cold weather. Therefore, ensure the unit receives regular and thorough maintenance services from HVAC experts. This will save you costly repairs and high energy bills. It will also protect your home from potential dangers that could threaten your family’s well-being.
9. Dirty Flame Sensor
Most contemporary gas furnaces have flame sensors installed. Over time, dust, carbon and other particles can build up on the sensor. This accumulation causes the device to corrode, making it difficult to sense the gas flames. A dirty sensor will cause the furnace to malfunction even after several ignition attempts. If you light the burner and the flame goes off instantly, you need to clean the flame sensor. The sensor can also break or wear out over time, and you’ll need a trained person for furnace repairs or an upgrade.
10. Check Your Gas Furnace Ignitor
Many modern gas furnaces have an electronic ignition system. When the ignitor becomes faulty, your furnace will not turn on to avoid gas leakage. As a safety precaution, you should keep track of the furnace ignitor. Check out for any damages and request the assistance of a professional when necessary. You should also ensure regular maintenance services to detect faultiness in good time.
11. Blower Motor Issues
A blower circulates the warm air from your gas furnace through the heat registers around your home. A faulty blower can hinder warm air from entering the house, even when the furnace is functional. The blower may have broken down or developed other defects over time. Debris accumulation can also obstructions causing the blower’s failure. If you notice odd noises or a burning smell from your blower, contact HVAC experts to help you identify the problem.
12. Gas Furnace Has Worn Out
Most gas furnaces have an estimated lifetime of about 15 to 20 years, after which you will need a replacement. A furnace that has exceeded its lifespan will become obsolete at some time, even after several repair and maintenance services. If your gas furnace breaks down often or fails to turn on, it’s time for a new installation. You can contact Main Street Heating & Cooling for advice or reviews about recent furnaces.
A defective gas furnace is the last thing to imagine when temperatures drop. The causes of the furnace breakdown mentioned above can help you make an informed decision and avoid further damage. Our highly skilled technicians at Main Street Heating & Cooling can diagnose and resolve small or large gas furnace problems.
We also provide heating, cooling, indoor air quality and commercial HVAC services to residents in Sandy, Utah, and the surrounding areas. Our customers’ needs are our priority, and you can reach us at any time of the day for emergency services. Do not hesitate to contact Main Street Heating & Cooling to schedule an appointment and let the experts restore comfort to your home.
