maintenance man checking furnace

Common Causes of a Whistling Furnace Noise

There are multiple heating options you have for your HVAC system. The furnace, however, remains the most popular choice. This is because it can run on different types of fuel and there have been various technologies to improve its energy efficiency.

At the moment, the furnace is one of the most energy-efficient heating options on the market. Though designed to enhance your level of comfort, there are times when the furnace will be the primary cause of your discomfort.

A noisy furnace is the most common cause of indoor discomfort related to an HVAC system, especially when it produces a whistling sound.

The following are the common causes of a whistling sound from your furnace.

Dirty Filters

A dirty air filter for the supply of heated air to your indoors might be the cause of a whistling sound. In this case, the heated air will struggle to pass the space left by the debris and dirt in your filters. Moreover, the sound comes from the in drawing of air from your interiors through mostly blocked air filters. Other than the noise generated by the dirty filters, the dirt also contributes to the wear and tear of your fan’s motor since it overworks to blow air through the small openings left on your filters.

A Defective Gas Supply Valve

This issue affects gas-powered furnace systems. If the gas valve is faulty, then this often causes the gas flowing through your system to come out at high pressure. The high gas pressure is the cause of the whistling sound. If you smell gas in your property, it is prudent to switch off the furnace while you wait for the repair technician to come and repair the valve. This not only alleviates gas wastage but also protects your property from fire and its occupants from the detrimental impact of inhaling the gas.

epair man performing maintenance

Ducts That Are Too Small

Improperly sized HVAC ducts are a common occurrence in systems that are not professionally installed. If your ducts are too small, then suction is created during the flow of air through your furnace. This suction manifests as a whistling sound and stops when you detach the furnace’s doors. If this is the issue causing the noise in your furnace, an overhaul of the ducts for others that are the proper size is the solution.

Leaking Air Ducts

Poor connection to your main ducting line and deteriorating ductwork are the common causes of leaks in HVAC units. The leaks waste your energy and will cause unnecessarily high energy costs. Depending on the extent of your ductwork’s deterioration and the age of your system, a replacement of the ducts might be the solution for your property.

A periodic furnace tune-up by professionals can detect the above issues. When picked up during the tune-up, fixing them takes a short time, making it cheaper than having to wait until they are evident as a whistling sound. A periodic tune-up is a critical element which saves you on costly repairs and prolongs your furnace’s functionality.

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