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Your Indianapolis Licensed HVAC Contractor


Your Indianapolis Licensed HVAC Contractor


Vital Heating & Air Blog

5 Furnace Warning Noises That Can Mean It Needs Repairs


Proper care for your home’s furnace with fall maintenance every year can prevent the majority of repairs the system may need over its service life. But you still need to be cautious and aware of issues that can arise with your furnace over the winter: the sooner you catch a potential trouble, the faster our technicians can repair it and the less large and costly it is likely to be.

Furnaces do not yet have full computer diagnostics that can alert you immediately to a specific trouble. They do have ways to warn you that something is wrong; you just have to know how to read the signals. One of the most common ways for a furnace to indicate trouble is with unusual sounds. If you’ve already spent one winter with your furnace, you know what sounds to expect from it. When something odd or loud interrupts those sounds, you may need to call us for service for your furnace in Indianapolis, IN. Below we’ve listed five common warnings sound to listen for.

1 – Rattling

This might be basic. Check the panel of the furnace cabinet to see if it’s loose. Some modern furnaces won’t run if the panel is open, so a loose door could lead to the system shutting down. But if the door isn’t the source, the rattling sound can mean a part is loose somewhere in the blower motor, or the furnace cabinet is coming loose from where it’s attached to the floor. 

2 – Mechanical shrieking

This is an alarming noise, but it’s also one that’s giving you a heads-up on how to stop an even bigger problem. This is the sound of the bearings in a motor in the furnace wearing down. When the bearings wear down entirely, it will soon cause irreparable damage to the motor. If you have technicians come in early to check on the issue, they can replace the bearings, which is a much less expensive repair than having to replace the entire motor.

3 – Mechanical grinding

This is the next step beyond shrieking. This usually means the motor itself is burning out and needs to be replaced. Shut off the furnace at the furnace switch (usually located on the wall near the furnace) and call for technicians. Don’t delay, especially if you can also smell an acrid electrical odor from the furnace.

4 – Sudden booming

This startling sound often means that there is something wrong with the burners or the ignition system. This booming is coming from a build-up of unburned gas inside the combustion chamber. When the burners finally light after the delay, a large amount of gas in the combustion chamber will ignite at once and create that sudden whoosh. You’ll want technicians on this problem since something is probably wrong with the burners. 

5 – Clicking

Some clicking as the burners start-up is normal. However, if you hear a clicking or rattling sound from the inside of the furnace after the blower shuts off, it may be warning you that there is a crack in the heat exchanger. This is a potentially harmful problem and must be corrected right away. Shut off the furnace and call our experts.

Your comfort is Vital, so always call Vital Heating & Air.

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