HVAC Odors And Heating And AC Repair: Different Smells And What To Do About Them | Rockwall, TX

HVAC Odors And Heating And AC Repair: Different Smells And What To Do About Them | Rockwall, TX

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In an area that experiences a lot of rain even in its driest months, temperatures in Rockwall, TX, can soar as high as 95°F in a day. When this happens, the last thing on your mind is a malfunctioning air conditioner or producing a foul smell. HVACs tend to produce odors from time to time, however, not all of them are cause for concern. Some odors predispose your family to serious health hazards; therefore, it is crucial to contact a heating and AC repair service when you identify any foul odors.

In this post, we point out a few HVAC odors you need to know and what you should do about them.

Rotten egg or a sulfur smell

Such a smell may mean that there is a decaying animal in the ductwork. Small animals such as birds, mice, and rats tend to get trapped inside. Once they die, the decomposing animal gives off a rotten smell.

The smell of rotten eggs emanating from your unit may also be a sign of a deadly natural gas leak. Although gas is odorless, utility providers add the smell so that people are alerted of a leak. A gas leak requires immediate attention. Exposure to low levels of this gas may reduce the oxygen levels in the blood resulting in loss of consciousness and, in severe cases, death.

As natural gas is highly flammable, open the windows and doors and evacuate the building immediately. Contact your heating and AC repair technician, your local gas provider, or the fire department.

Burning or scorching smell

Most Rockwall, Texas, do not see the need to switch their HVAC units to “Heating Mode.” When winter begins, and the need to heat their homes arises, most of them notice a burning or scorching smell.

When your HVAC is not in use, the heating system gathers dust and dirt. Therefore, a burning smell from your unit is not uncommon immediately after you switch it on. However, the smell should dissipate within a few minutes or hours of using your unit. If this does not happen, the burning smell may be as a result of:

  • A malfunctioned fan belt – If squealing noises accompany the burning smell, this may signify a broken or malfunctioned fan belt. This is mainly caused by the intrusion of debris or the belt wearing off due to age.


  • An overheating motor – Eventually, the bearings on the fan’s motor will wear off because of extended use. When the motor overheats, you may notice the smell of burning plastic coming from your unit. Your preferred HVAC repair technician can easily resolve this issue by lubricating the bearings.

Any electrical and mechanical problems with your HVAC needs to be handled by a qualified HVAC repair technician. Handling them on your own may lead to severe injuries.

Chemical smell

A chemical smell coming from your unit may be as a result of:

  • Refrigerant leak – This is what absorbs the heat from the air that is drawn into the unit. Due to the inevitable wear and tear, the copper coils that hold the refrigerant may crack, thus causing leaks. Such a leak not only affects your unit’s performance but also poses a serious health risk.


  • Household chemical containers near the air handler – If the odd smell is that of a household chemical or cleaning product, it may be because of storing containers that had such near the air handler. Fumes are then drawn into the unit and blown throughout your space.


  • Recently done ductwork – If you’ve had the unit’s ductwork repaired recently, the glue used may give off a chemical odor as it dries.

Whatever the cause of the chemical smell, it is a good idea to have it addressed by a heating and AC repair technician immediately.

Musty smell

Musty smells are among the most common odors in HVAC systems. This smell could be due to a dirty evaporator coil that becomes the perfect breeding ground for mold. If this issue occurs repeatedly, your heating and AC repair technician may recommend that you install a UV lamp that kills any mold and mildew.

A musty odor may also mean that your unit’s drip pan is worn. The drip pan is where the water droplets from the cooled humid air are collected. As with any part of your unit, the drip pan is susceptible to wear and tear. A worn drip pan will lead to the growth of mold and mildew, thus the musty smell. Your heating and AC repair should be able to replace it and recommend the most effective mold and mildew remover.

Dirty socks odor

You may notice the smell of dirty socks or stinky feet when you switch on your unit after a long time. Also known as the “dirty sock syndrome,” this happens when dirt, dust, debris, and moisture accumulate on the unit’s evaporator coils providing the perfect breeding ground for bacteria.

Your heating and AC repair technician can resolve this issue by draining and repairing the unit’s drainage system, cleaning the evaporator coils, and replacing the air filters.

Oily odor

An oily odor may be either caused by a malfunctioning oil burner or an oil leak. The oil burner could malfunction if it becomes clogged or due to a damaged fuel pump. Apart from the smell, problems with the oil burner are characterized by smoke and soot around the unit. In case of an oil leak, the problem can be resolved by repairing, replacing, or tightening the oil line. If you think you have a problem with the oil burner or have an oil leak, contact a qualified heating and AC repair technician to address the problem.

In a nutshell, most of these smells may mean that you need heating and AC repair services. Gas and a burning odor may be a sign of a serious underlying issue. In that case, shut down the unit immediately and contact your heating and AC repair technician. At K&S Heating & Air, we are the leading HVAC heating and AC repair service in Rockwall, TX. Our technicians are not only trained, but they are also friendly, personable, and have a thorough knowledge of Rockwall, Texas, to ensure that they get to you within no time. Get in touch with us today for more information about our services.