My Furnace Won't Ignite

5 Reasons Why Your Furnace Won't Ignite

Furnace having trouble igniting?

Majority of homes in GTA uses forced air gas furnace to create and distribute heat. Typical lifespan of furnace is 10-15 years before needing to be replaced. There are several reasons why furnace wont ignite. Lets read through and get idea what can be some common causes for furnace not igniting. Contact our professional service to help you with your heating problem today!

Why won't my furnace ignite?

1. Gas Line Issues

Type of natural gas problem include gas leaks, blocked gas line & defective gas valve. Its important if you smell gas (Mercaptan Smell; resembles rotting cabbage or garlic) at any point, exit your home and notify your gas company.

2. Defective Thermostat

For furnace to ignite we have to set thermostat to heat. If its not, your furnace won't ignite. Another possibility is the thermostat connections or sensors are defective. If you set furnace to heat and still no operation thats concerning and HVAC specialist should be notified.

3. Dirty Furnace Filter

If your furnace filters isn't replaced regularly allowing more dirt and little particle lay on the filter clogging it to point where air cannot pass freely will cause major malfunctions to your furnace preventing improper airflow through the system which is necessary to ignite the furnace. We recommend to inspect furnace filter every 30 days and replace if needed.

4. Defective Igniter

If your furnace won't ignite, we may be facing a broken ignitor. Most furnaces have an electronic system to ignite the burners. A dirty or burned ignitor can prevent the burners from igniting. If you're noticing clicking sound without any sort of ignition have specialist diagnose your furnace and determine the cause.

5. Dirty Gas Burner

Having a dirty burner may prevent furnace from producing any heat. To much dirt can cause burners to shut off. We highly recommend every homeowner to do annual furnace maintenance to make sure the furnace is clean, safe and ready for upcoming winter season.

3 Types of Furnace Ignition System

1. Standing Pilot Light

Gas Valve has a knob which reads "OFF/ON/PILOT" This type of furnace contains thermocouple which is a heating sensing tool. Thermocouple ensures that gas reaches the burners only when the pilot light warms the thermocouple.

2. Intermittent Pilot Igniter

Intermittent pilot is similar to standing pilot light. The intermittent pilot uses a pilot flame, the difference between intermittent and stand pilot is the pilot igniter comes on only when the thermostat calls for heat and sends signal for the heat to turn on. Operation for intermittent pilot follows as control board signal’s igniter > Igniter turns on the pilot flame > pilot flame turns on the gas > thermostat is satisfied furnace shuts off & pilot flame deactivates

3. Hot Surface Ignition

Majority of furnace nowadays contain HSI ignitor (Hot Surface Ignition). The HSI attachment has a fork look with two wires connected. When the Thermostat calls for heat, HSI gets energized and heats up. As the HSI reaches maximum temperature the furnace signals the gas valve to open and ignites the gas.

Conclusion

As homeowner our first go to source is researching why my furnace won't ignite or why my furnace wont turn on. As much as you try to find answers on google the problem of defective furnace is endless. Its recommended to contact a licensed professional whom dedicate their time and life in the trade to perform work on these appliances. Contact us for professional furnace repair service with same day HVAC service or call your local HVAC specialist.