HVAC System Smells | Chrismon Heating & Cooling

Lady pinching her nose

Your HVAC system should maintain comfort in your residence regardless of external temperatures. A reliable HVAC unit can operate smoothly for an extended duration, but instances may arise when the system signals a need for repair. If you notice any odors emanating from your home, engage an HVAC specialist for further examination.

Moldy, Dusty ACs

Musty odors in AC units are often from dirty filters, dust in ducted systems, and water accumulation in drain pans or drip lines. These conditions can lead to the growth of mold, mildew, and fungus, resulting in an unpleasant odor.

Additionally, turning on an AC after a long period of disuse in a hot and humid climate can cause moisture accumulation within the system, contributing to mold and mildew development. If you notice water dripping down walls from an indoor ductless unit or suspect a leak, contact a professional HVAC technician.

They can thoroughly inspect and clean your air conditioning system's lines, ducts, and other components. Fixing leaks and ensuring proper drainage will help prevent moisture-related issues and the associated foul smell.

Electrical Odors

HVAC systems have electrical components like motors, transformers, and circuit boards. If these components become overheated due to excessive electrical current or poor ventilation, they can emit a distinct burning or electrical odor. Worn-out bearings, dust accumulation, or inadequate lubrication can cause overheating.

Worn or damaged electrical wiring can lead to short circuits or overheating. When wires are exposed to excess heat, their insulation can melt or burn, resulting in a noticeable smell of burning plastic or rubber.

Rotten Eggs

The smell of rotten eggs in HVAC systems usually indicates a gas leak, specifically a leak of natural gas or propane. Natural gas and propane are naturally odorless and colorless gasses. Gas manufacturers add an odorant to these gasses to make it easier to detect leaks.

Gas leaks can occur in various parts of the HVAC system, such as gas supply lines, connections, valves, or even the furnace or boiler. Multiple factors, including corrosion, wear and tear, poor installation, or faulty equipment, can cause leaks.

Blocked vents or exhausts can also impede the proper flow of gases, leading to a buildup of gases within the system. This buildup can release unpleasant odors, including the rotten egg smell, into the indoor air. Another cause is back-drafting, which occurs when exhaust gasses are not properly vented outside, causing them to flow back into the living space.

Oily Smell

HVAC systems use refrigerants to cool the air. If there's a refrigerant leak, the escaping refrigerant can emit a distinct oily smell. Refrigerants often contain lubricating oil, and the odor can be particularly noticeable near the vents. A refrigerant leak affects system efficiency and poses environmental and health risks.

The compressor also contains oil to lubricate its moving parts. If there's an oil leak within the compressor or its associated components, such as gaskets or seals, the escaping oil can produce an oily odor when heated during the system's operation.

Burnt Smoke

When air filters become clogged with dust, debris, or other contaminants, they can restrict airflow through the HVAC system. This can cause the system to work harder, potentially leading to overheating components and producing a burnt smell.

Foreign objects such as leaves, plastic, or other debris can sometimes get lodged in the HVAC system. When these objects come into contact with heated components, they can melt or burn, producing a noticeable odor.

Chrismon Heating & Cooling offers trusted HVAC services in Greensboro, NC, treating clients like family. We provide stress-free installation and repair, guiding customers with informed recommendations and education for optimal comfort year-round. We are trusted by local homeowners and businesses for heating and air conditioning needs. Get in touch today.