Furnace Won’t Turn On? Here’s What To Do!

Proudly | Carrying

Johnwood logo
Navien logo
Goodman Logo
Daikin Logo
Armana logo
Armana logo

Furnace won’t turn on?

Not to worry, here at Burford Heating and Air Conditioning, we’re going to outline exactly what steps you need to take to ease any furnace problems you’re experiencing.

Okay, so if you’ve ever found yourself freezing in your own home during the winter and your furnace isn’t producing warm air, asking yourself the question, “Why won’t my furnace turn on?” you’re most likely very eager to get to the bottom of why your furnace or heater won’t kick on. 

Using these tips, you’ll be able to gain an understanding of why your furnace won’t turn on in no time. 

Understanding How Your Furnace Functions

Understanding how a furnace works is the first and most essential step in troubleshooting why your furnace unit won’t start.

Although there are a few different varieties of furnaces available, the most common type are natural gas furnaces.

A furnace is part of your home’s HVAC (heating, ventilation, and air conditioning) system. When you set your thermostat and the system temperature, the heat exchanger in your furnace unit should start warming air to the desired temperature, while a fan system spreads the heated air throughout your home.

If you notice that your heater won’t turn on with the thermostat, you’ll know that this is a furnace issue rather than an issue with the other parts of the HVAC system.

Troubleshooting Steps For a Furnace Not Turning On [Common Furnace Problems]

Before reaching out to a professional to request an HVAC service call at your house to determine why your heat won’t turn on, there are a couple of steps you can take (ONLY if you feel 100% comfortable about your safety doing so) as sometimes the furnace repair CAN be an easy fix.

However, if you have ANY level of discomfort or concern, we highly recommend calling a professional HVAC technician immediately and they will help you get your heating system to function properly.

Check the Furnace Air Filter

The air filter is located within the blower compartment of the furnace. If this essential part of the furnaces system becomes clogged with dirt or dust, it can shorten your furnace’s lifespan and cause it not to turn on. 

Not only will a clogged filter be the cause of your freezing home, but it can also become a fire hazard and even worsen air quality. 

To safely check and clean the filter, turn your thermostat and furnace off and depending on the level of dust within the filter, either clean or replace it entirely. Depending on the furnace, you might need to remove the furnaces front panel to complete this step.

Furnace filters should be checked every 30 days to ensure your furnace functions at peak conditions. The possible health hazards that could come from a clogged furnace filter should also motivate you to check in now and again.

Check The Thermostat

Another one of these easy fixes to check off your furnace troubleshooting checklist should be checking the thermostat. 

There are many thermostats, but most are similar and have very similar controls. Check the thermostat’s settings, ensure it is set to the desired heating temperature, replace the batteries (you’d be surprised how often replacing the batteries resolves a broken furnace.) Also, give the inside of the thermostat a dusting. Keep in mind that your thermostat should be away from direct sunlight or other heating sources to avoid false readings. If the furnace will not turn on following these thermostat steps, then move on to the next step.

Check The Furnace Power Source

If the thermostat and filter aren’t the problems with your furnace, the next step is to check the power source as it can often be just a tripped circuit breaker.

You will have to look at the power source to ensure there isn’t an issue with the electrical connection, and the power source is sending power to the furnace and the furnace is receiving power.

First, try flipping the furnace switch on and off. If this doesn’t work, search for the electrical box. 

Keep in mind that doing anything with your house’s electrical box can be dangerous. If you are not comfortable, be sure to contact an electric company or qualified electrician right away. 

Once you’ve located the electrical circuit breaker box, make sure the HVAC circuit breakers power switch is on. If the circuit breakers power switch isn’t on, flip the breaker switch all the way off before flipping the switch into the “on” position. 

If your electrical box doesn’t have power, there could be an issue with its cords. Look for melted and discoloured fuses to replace. 

Fuse replacements can be tricky. Be sure to safely remove the cord and find an identical one at a hardware store to have a functioning electrical box.

Look at the Furnace Flame Sensor/Ignition Sensor

This sensor is located near the bottom of the furnace in the burner assembly and looks like a thin metal rod.

If your fsensor is any colour other than blue, this could be why your heater won’t turn on. 

If your furnace flame sensor is red, green, or yellow, contact a local HVAC company immediately.

Also, a dirty ignition sensor can also be the cause of a broken furnace. The dirt or grime can cause a dirty sensor to properly perform. To clean it remove the screw beside the sensor and then slide the ignition sensor from its current position. Following this, gently clean the metal rod with steel wool. If there is a lot of grime built up, you can use a straight edge knife to gently scrape it off. Once clean, you can reinsert the sensor back into place, and test the furnace to see if it is now producing heat.

Look at the Vents, Air Ducts and Registers

Around your house, there should be several supply and return grills.

If these vents or air ducts are obstructed in any way by furniture or fabric, they can lead to excessive air pressure and the overall breakdown of your entire HVAC system.

This is another cause of possibly why your heating system won’t kick on that you should be checking regularly to avoid unwanted consequences.

Check the Blower Motor

Following the heat exchanger heating the air, the blower motor and the fan system push the warm air through the house. If your blower motor isn’t working, heated air will not be able to circulate around your house, and your furnace won’t turn on automatically.

If this is the case, a professional HVAC contractor will need to come for a furnace repair service call and evaluate the level of damage on the motor. This can be expensive but is easily fixable. 

Check the Gas, Furnace Pilot Light

The last stop on your “my furnace won’t turn on” troubleshooting checklist is checking the gas and pilot light. 

The pilot light, and gas valves should be located near each other at the bottom of the furnace. If the pilot light has gone out, you will need to relight it. This is a common reason for a gas furnace not working, as the pilot light must stay lit for the furnace to work.

Turn the gas off for about 10-15 minutes before doing this.

Also, keep in mind that if you have a gas stove or other appliances that use gas and they are functioning properly, it likely isn’t gas line.

Keep in mind this is not a step that should be taken lightly. If you smell gas or have any concerns, evacuate the home immediately and call a gas company, gas technician, or even an HVAC contractor depending on where you’re located. They will check the gas furnace, the gas valve, the gas line and gas supply and ensure everything is running properly and safely.

My Furnace Won’t Turn On – Final Thoughts 

If you find yourself staring at a Google search bar with the words, “furnace not turning on, heater not turning on, or how to fix a furnace that won’t start.”, this article should help your freezing fingers find a solution fast. 

Unfortunately, if you have gone through the “my heater won’t turn on” checklist and your furnace still won’t come on, call a professional. If you’re in Southwestern Ontario, we invite you give us a call here at Burford Heating for furnace repair services. However, if you aren’t within our HVAC service area and you’re unsure of how to select a qualified HVAC technician, we recommend reading our article “How to Choose an HVAC Contractor.”

Although it is excellent to know how your furnace works, and some simple tricks on how to deal with a broken furnace, you are still working with gas and electricity, both of which can seriously harm anyone who doesn’t feel %100 confident in their abilities to take these step safely. We highly recommend most homeowners call an HVAC technician for any type of heating system (ie. A heat pump, fireplaces, boilers,etc.) or furnace repair.

So, if this happens to you, make a cup of hot chocolate and curl up with a blanket in one hand and your phone in the other and call a professional residential HVAC Company to complete the furnace repair and ensure it working properly and bring comfortable living back into your life.



*On Approved Credit- Residential Customers Only




Low Easy Monthly Costs


Complete Equipment Coverage


Experience Stress-Free Home Comfort


Rate Increase Protection


Clear and Transparent Terms


Flexible Financing Options


Only Work with Burford Heating Techs


Easy Credit Approval Process


Complete Repair and Warranty Coverage

Find out what financing options we have for your residential HVAC needs. Click the button below to apply now!

*Approval Not Guaranteed. Not all financing offers available on all services. Call for details.

HVAC Financing For Less Than The Price of a Coffee Per Day!

Goodman Logo
Lennox Logo
Rheem Logo
Carrier Logo
Carrier Logo

Burford Heating and AC Provides Services to Burford and the Following Areas

Call Your Local Neighbourhood HVAC Experts

Get In Touch



Burford Heating and AC 233 Oakland Rd Scotland ON N0E 1R0

Google Rating
Based on 26 reviews

Follow Us


Call icon

Like Us