Through normal wear and tear or problems during installation, there are times when a lot of rattling and loud banging can come from the heating unit. There's a few areas that require inspection, but the ductwork and fan system are the most common. As you look through the heating system for issues, consider a few inspection and repair options that could take care of the noises once and for all.
What Kind Of Noise Is It?
The type of noise can give you a good indicator of the general problem. Frequency (pitch and how often the noise happens) and volume should be taken into consideration as you turn the system on and off.
If there's noise all of the time when operating the heater, you likely have a problem with the ductwork being loose. Loose ductwork can rattle with the movement of the heater fan and other moving parts, which translates to a rumbling noise that can drown out casual conversation.
Ductwork is hollow metal and can become a loud, echoing percussion instrument in such situations. The cause of the problem is often a lack of clearance area between the ductwork, heating unit and walls. There are noise dampeners that can be installed or pinning techniques to keep ductwork against the walls in tight spaces, but best practice is to keep the heating unit and ducts far enough away from the walls to avoid collision and subsequent vibrations.
If the noise seems to be intermittent and regular, such as a tapping or scraping in regular patterns, it may be the blower fan inside the heating unit. The blower fan is responsible for distributing warm air through the system in order to deliver comfort to you, and is susceptible to dust settling over time.
Fan Imbalance And Failure Requires Deeper Maintenance
If too much dust settles on a specific fan blade (or impeller in certain blower types), the fan may begin to scrape and slap against its housing. The issue can become a quiet hissing noise if contact is light, or a loud, distracting banging if the fan strikes hard enough.
A fan that hits its housing for too long may eventually lose some of the metal, which can make the entire fan unit unstable. With a different weight on one of the fan blades, the fan can begin to wobble or even work itself off of its axis, leading to a much bigger repair need.
Working inside a heating system can be dangerous because of the electrical contacts and the depth that needs to be reached by taking the unit apart. Contact a heating repair professional as soon as possible to fix the fan problem and other heating unit issues before the system gets worse.