Plumbing and Heating Services in Calgary | Wiehler Mechanical

3 Furnace Noises You Shouldn’t Ignore

Eric Wiehler

You don’t care much about your furnace until it breaks down. Luckily, your heating system is likely to produce one or more warning signs that an HVAC service is on the way, and knowing what to look for can make the difference between a speedy repair and an expensive one.   


Table of Content- 


  • Overview  
  • Banging  
  • Squealing  
  • Scraping  
  • Hire us for furnace repair or replacement  


Unusual sounds, which vary from the normal noises associated with start-up or the engine’s buzz, are amongst the prevalent indicators of a malfunctioning furnace. While the majority of noises are harmless, there are a few that you should be aware of, including the three sounds described below.  




When your furnace receives a request for heat from the thermostat, it reaches its peak. The burners ignite once the fuel supplies to burn them, and heat production begins. If your furnace starts up with a loud bang, boom, or popping sound, you must determine the source and call a professional to fix the problem. The following are examples of possible causes: 


Duct expansion: The expansion and contraction of metal ducting due to changing temperatures is likely the source of a loud banging noise coming from several feet distant from the furnace. Of course, the metal heats and cools as the furnace blower cycles on and off, and the rules of physics implement, but excessive expansion and the resulting noise might be a symptom of one or more difficulties that require expert care. The following are examples of possible causes:  


  • Clogged air filter  
  • Closed vents  
  • Low-quality ductwork  
  • Undersized ducts  


Dirty furnace burners: A dusty or mistreated furnace can contribute to many problems, including delayed ignition due to dirt build-up on the furnace burners. When required for the dirt to burn away, gas fumes might build-up to the point where they can create a minor explosion when burned, endangering the heat exchanger’s integrity. The expert will examine, tune, and clean your furnace, including the burners, as part of periodic heating maintenance.  




A substantial squeal or scream arising from your furnace should check further since it might be caused by:  

  • A blower belt that has worn out is sliding or has gotten loose.  
  • A fan mower that has stopped working.  
  • Bearings on shafts need to lubricate.  





The sound of metal striking metal indicates that the blower wheel is defective. Keeping the furnace running can cause serious harm. Therefore, it should turn off at the first hint of noise, and a professional notified right away.  


The following are some of the most common blower wheel issues:  

  • The motor mount, which is supposed to keep the blower component in place, is broken.  
  • A cracked blower wheel. 
  • The noise might be produced by the wheel impacting the casing, and if no severe damage has happened, the expert may be able to tighten the wheel back up quickly.  


Hire Us for Furnace Repair or Replacement 


For high-quality, reliable furnace services, such as furnace installation, maintenance, or repair, rely on our furnace repairman at Wiehler Mechanical. Book us today to set up an appointment and tell us how we can assist you.