Interpreting Three Common Gas Furnace Noises

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Like all mechanical equipment, your furnace speaks its own language. If you spend enough time listening, you can learn what your furnace is trying to tell you. A typical furnace that's correctly operating may make very little noise. Depending on where you've placed your furnace in your home, you may only hear the sound of your blower motors turning on or air rushing through your vents.

However, it's sometimes crucial to listen a little more closely. If your furnace is working poorly, inefficiently, or not at all, you may want to head down to your basement or crawl space and hear what it has to say. These three common sounds may be cries for help.

1. Clicking Sounds

There are a few potential sources for clicking sounds in your furnace. Some may be normal, such as the gas valve opening when a thermostat calls for heat. If you hear a click right before your furnace starts, but everything seems to be operating just fine, it's likely not a concern. However, some clicks may indicate brewing trouble.

One possible source for a clicking sound is the fan capacitor. Your furnace needs the fan capacitor to provide the initial "juice" to get the blower motor turning. A faulty capacitor may struggle to move the fan motor, resulting in a clicking sound. If you hear several clicks before your fan starts running, or the fan never turns on, your capacitor may be to blame.

2. Scraping or Grinding Noises

Scraping and grinding noises usually indicate a mechanical issue with a moving component, such as the blower or inducer motors. Try to determine when you first hear these noises. A typical residential furnace follows a tight order of operations, which includes activating the draft inducer motor before the house blower engages.

If you hear the sounds before your furnace begins producing heat, you're probably hearing a problem with your inducer motor. Even if the blower still works, loud noises likely indicate failing bearings, and your draft inducer may not last for much longer. If you only hear the sounds once you can feel moving air from your vents, the house blower is a more likely culprit.

3. Sudden Bangs

Some crackling and popping may be normal in homes with rigid metal ductwork. While you can take some steps to mitigate particularly noisy ductwork, it's nothing to worry about in most cases, and you're usually only hearing the sound of expanding metal. On the other hand, a loud bang or the sound of an explosion as your furnace turns on can mean trouble.

If you've ever had to wait for a gas stove to ignite only for the flame to roar to life suddenly, the same thing may be happening in your furnace. Dirty burners can allow some excess fuel to build up, igniting a larger than normal flame. While this situation usually isn't dangerous, you should have an HVAC technician investigate as soon as possible since it can damage your burners.  

contact a company like HEATCOOL 1 for more information about residential heating. 

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20 December 2021

preparing your furnace for winter

I know it can be difficult to make yourself think about getting your furnace running when the skies are sunny and the temperatures are hovering around 90, but it is the best time for you to think about your heating system. Getting ahead of the winter preparation game will help to save on the cost of the repairs because the need for furnace maintenance is usually at a low during the fall season. This blog will show you what you can do to prepare your furnace for winter and when you should hire a professional HVAC technician to take care of it for you.