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Is Your Furnace Making Noises? 5 Sounds Your Furnace Should Never Make

furnace making noises

What’s that sound coming from your furnace? Some noises are completely normal, especially if your home has an older model. But other loud noises, such as banging or squealing, can signal that it’s time for a repair or replacement.

Like most southern states, Texas stays warm for most of the year. Regardless, during those few weeks of winter, you’ll want to make sure your heating, ventilation and air conditioning system is in working order. If your family depends on a furnace to keep your home warm during winter, keeping it properly maintained throughout the year is important.

Is Your Furnace Making Noises?

When furnaces begin making certain noises, it often means that something isn’t working properly and you should take action to get it fixed right away. There are many reasons this could be happening, so you’ll need to pay close attention to the type of noise your furnace is making so that you can better diagnose the problem.

Screeching or Scraping Sound

One of the most common noises that furnaces begin to make when something is going wrong is a bird-like chirping sound which could even be compared to the sound of metal scraping metal. Hearing this noise in your home could signal an issue with the motor or the blower wheel. If either one or both of these furnace parts are broken, the noise you hear could be caused by the assembly hitting the furnace casing.

Loud Boom

If your unit is making loud boom-like noises, it’s often an indication of dirty burners within your furnace. The dirt causes a delay when igniting, which leads to excessive gas buildup, so when the burners finally do light, it creates that loud banging noise you hear. Although these are essentially small explosions, don’t ignore them, because these blasts could crack the heat exchanger, which means more money spent on repairs. Eventually, dirty burners can become dangerous because they can lead to carbon monoxide leaks.

If your furnace has metal ducts, a similar noise can occur because the ducts contract and expand as the blower turns on and off. Undersized ducts, closed vents or clogged air filters are usually the culprit.

Constant Clicking Noise

In this case, the igniters are working to try to light the burners or light pilot, but can’t due to a malfunction with the ignition system. The ignition system is essential to your furnace because it’s what starts (ignites) the burners that heat your air. Some of the more common problems with ignition systems include:

  • Flame issues, due to an incorrect mixture of gas and air.
  • A malfunctioning or thermocouple (the flame sensor) that’s covered in soot, which prevents it from detecting the pilot light to shut the gas valve.
  • A faulty gas valve that isn’t energized, so it won’t open because of an issue between the ignition board and the valve.

Rattling or Clanking

When furnaces make clanking or rattling noises, it could indicate loose ducts, or even that the furnace itself is sitting on an uneven surface. Examine the area where the furnace is in your home to determine if that’s the issue. If the furnace rattles when it turns off, this could be the sound coming ¬†from the metal parts of the furnace cooling down.

Squealing Sounds

High-pitched squealing sounds coming from your furnace often mean there is a problem with the blower belt due to it being loose or slipping, or that the blower motor itself is malfunctioning. If belts become loose or broken, they can begin hitting other parts in the furnace, causing further damage to the unit. The shaft bearings on your unit may need oil, which could produce a squeaking noise. Although this problem isn’t as pressing as the others, your safest bet is to have your furnace checked out to make sure it isn’t something more serious.

Tips for Better Furnace Maintenance

After you identify the noise coming from your furnace, there are some steps you can take to get your furnace back into shape. With some regular maintenance, you can keep your furnace running for years before having to replace it altogether. To keep your unit maintained, take the time to:

  • Clean and replace the filter system.
  • Check the thermostat.
  • Clean and repair your furnace ducts.
  • Clean the vents.
  • Give it a thorough inspection annually.

Call a Professional to Help

Being aware of these sounds can help you avoid costly repairs. At ABC Home & Commercial Services, our trained experts have the experience and knowledge required to repair your furnace and get it back in top condition. Whether it’s a quick fix or setting up annual maintenance, ABC has you covered.

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