9 Common Causes Why Your Furnace At Home Is Not Working

Furnaces in homes are typically extremely dependable. However, they might be finicky and stop working at times. What causes a furnace to break down? The problems range from minor and simple to more complicated and require professional assistance.

If you’re experiencing a similar issue, it’s good that you’ve found this blog, as it will discuss some tips to help you resolve your problem. Read on to learn what causes a furnace to stop working so that you know when to seek assistance from heating services in Santa Fe. 

9 Common Causes of Furnace Not Working

A Faulty Limit Switch

For your protection, the limit switch monitors temperatures within the furnace. A furnace can stop working if the switch fails. A technician will need to repair this component.

Cycles of the Furnace On And Off

Short cycling occurs when a furnace switches on and off quickly, which can cause damage. Clogged filters and airflow are common causes of short cycling; check and replace the filter and make sure all vents are clear.

Faulty components and incorrectly sized systems also cause this issue. Contact your HVAC specialist to evaluate the furnace source and determine the source of brief cycling.

Crack in the Heat Exchanger

The heat exchanger in your furnace transports heat from combustion to the air. Cracks or other damage to your furnace might cause it to consume more energy over time and years of frequent operation.

Cracks in your home’s foundation allow combustion gases to build, potentially resulting in dangerous carbon monoxide leaks.

It’s critical to have an HVAC specialist out right away to evaluate if a heat exchanger breakdown is a problem because of the potential for injury.

If you see any of the following, your heat exchanger is most likely the source of your furnace problem:

  • A foul odor emanates from your furnace when it is turned on.
  • Your home’s surfaces appear to be dirtier. This results from your furnace discharging soot into the air due to inefficient combustion.

Filter Is Clogged

A blocked air filter restricts the airflow through the furnace. Because the safety switch shuts the unit off when high temperatures are reached, leading to overheating and the system shutting down.

Check the filter for debris and replace it if necessary. Allow the system to cool down before checking to see if it starts up again.

Furnace Access Panel Isn’t Working Properly

Some furnaces have safety features that can force them to shut down. The furnace will not start if the access panels are not correctly fastened to the unit.

Examine the furnace’s exterior to ensure that all access panels are securely in place.

Igniter Error

This might cause a furnace to stop working if the igniter is faulty. Heat will not be generated by igniting the fuel. Check if the igniter needs to be replaced by:

  • Disconnecting the furnace’s power and removing the access panel.
  • Checking for apparent damage such as chips, fractures, warping, or fraying on the igniter.
  • Checking the igniter plug using a multimeter. The igniter must be replaced if it reads zero or infinity.

Not Properly Lubricated Furnace

If your furnace makes grinding noises while running, it’s a sign that the bearings in the motor aren’t oiled properly. Friction damages these components without appropriate lubrication, causing your furnace to shut down.

This is a problem that is addressed during annual furnace maintenance. To avoid harming your furnace, turn it off and leave it off until repairs are performed. Call today to schedule service, which includes maintenance of the motor bearings in your furnace.

The Circuit Breaker Was Tripped

A tripped circuit breaker can disable your heating system’s critical components. Check the circuit breaker if your furnace isn’t working. Breakers that have been tripped should be reset.

If the problem persists, there is an underlying problem that will continue to recur. Contact an HVAC specialist who offers furnace repair in Santa Fe, NM, to identify and resolve the issue. 

Thermostat Is Not Turned On

Your thermostat controls your heating system. One of the explanations why your furnace is not switching on is if its settings or communications have been disrupted.

Check the thermostat if your furnace stops working:

  • Double-check your thermostat settings: is it turned on and in HEAT mode? Is the set temperature a few degrees over the present room temperature to start a heating cycle?
  • Is it necessary to replace the thermostat’s batteries?
  • Has the breaker tripped if it’s hardwired?


Now that you recognize the possible causes of a broken furnace, it’s time to call a professional HVAC service specialist to fix the problem. With their heating repairs in Santa Fe, they will swiftly decide whether the damage can be repaired or if a new heat exchanger would be more efficient and safer for your furnace.

You will find a variety of plumbing and HVAC expertise at Lobo Tech. We deliver exceptional service at reasonable pricing, based on our more than 30 years of experience. Contact us today if you’re looking for a furnace repair in Santa Fe, NM

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