What Causes Ducts Noises in My Furnace
Posted on October 30, 2018
Furnaces are some of the indispensable HVAC systems particularly during the cold season. At the peak of winter, your family needs to stay warm and one of the best gifts you can ever give them is a fully functional furnace system.
While many homeowners try all they can to keep their furnaces in shape for the winter season, there are one or two things that may go unchecked and this may be a cause of problems once the furnaces are turned on. One of the problems that have been cited by a number of homeowners is the duct noises they hear once their furnaces come on.
The Likely Causes
One of the ways furnaces communicate the existence of a problem within the system is through the noises they make. If your furnace goes on and you realize noise in the ducts, a number of things could be behind this. If you are a DIY expert, you could conduct a preliminary check before calling a professional to fix the problem. This is because some of these issues are much simpler to fix and you can comfortably handle them.
Undersized Ductwork
This is one of the problems explaining duct noises. Basically, undersized ductwork makes the supply side ducts to expand when they pressurize. The result of this is that on the return side, a small vacuum is created.
When the blower turns on, the tin ducts will start making some sort of a banging sound. On the other hand, the expansion and contraction between the ductwork and the hangers causes the other ticking noises. The best solution for this is to insulate the ductwork using rubber cushions and this will cut down on the noise or even stop it completely.
Linking the Internal and External Components
By design, the external and internal components carry lots of acoustic noise. If these are put on the same path, the ductwork will act as a conduit and ferry all the acoustic vibrations into your home. This is when you will start hearing buzzing, howling, and whining noises which should otherwise not be heard. To solve this, the internal duct system needs to be delinked and put on different pathways with the external system.
The Return Air Part is Starving for Air
When the return air component of your HVAC system is starving for air, the plenum will cause banging noises. Every furnace manufacturer gives a temperature rise number which they expect to see from the system. When you check your furnace unit by taking a reading of the supply and return air temperature and then comparing this with the manufacturer’s requirement, you can know whether or not you have enough return air. If the temperature is too high, it may point towards a return air starvation. This problem if not solved in good time can shorten the lifespan of your furnace and increase the frequency of repairs and maintenance.
In addition to the above, it is very important that your ductwork is regularly cleaned and maintained so that debris and dirt buildup can be kept in check.