Top Reasons Why an AC SMELLS MUSTY & Best Solutions

Think that when you come home in hot weather and on the ac unit you have a smell and force to stop ac unit. There can be different causes why your AC smells MUSTY. We will cover different details for ac smells and learn how to remove smell from the ac unit. So let’s get started with Top Reasons Why an AC SMELLS MUSTY & Best Solutions.

How  Air Conditioning System Works

The working operation of ac unit will help to find the reason for must smell. it will be new to you that cannot create the cool but. But when the thermostat senses that the house temperature is not according to its display, the signal moves to the outside condenser of the AC. As a result, the condenser gets power from the device which is a capacitor. Using this power compressor of condenser transfer refrigerant in the indoor unit evaporator coil.

The pressure of refrigerant and temperate are low in the evaporator coil, cooling the coil. As a result, your room’s warm air goes to the indoor unit through supply ducts and blows through the coil. So refrigerant removes heat from the air.

To complete the process the cooled air goes to the home when the hot refrigerant moves to the condenser. The outdoor unit fan releases refrigerant heat to the environment.


Read also: Why Is My Outside AC Unit Not Turning On?

Symptoms Of Musty AC Smells

  • When you are on the AC unit firstly there can be a smell musty for some days. Sometimes it is removed after some time.
  • But the smell can be removed also after some days. But ac unit continuously smelling musty during working. It means there can be some error in your unit.

Types of Air Conditioner Musty Smells, Causes & Solutions

  1. AC unit not working ion inner combustion engine. So there are causes why that AC unit must smell like running car exhaust. But ac unit does not ensure to use of fluids and when gets heated have smells like exhaust fumes. The ac smell can be due to a leak in the refrigerant line. The refrigerant is a cooling material in the aircon, and any leak can affect the operation of ac unit.  It also releases chemicals in the air that can have a bad effect on the environment.  Frean and chlorofluorocarbons are mostly used as refrigerants in AC units, and they slowly operate.  Freon absorbs heat from indoor air that is released outside. It can be bad for the environment. So must check the freon leak. The free leak smell will be like chloroform or car coolant with a sweetish smell.  In some cases can be odorless.  If your AC releases a smell like a chemical must checked with the technician. The freon leak can be bad repair it as soon as possible. Make sure that your home is ventilated. it will release the smell and also save you from chemical hazardous effects.
  2. There is another common smell of AC units that is stale or dingy smee. If ac smells musty the normal case is water storage in a drain pan that causes fungus. If there is leakage there is a visible symbol in the indoor ductless unit, like water dripping down. This type of smell can be due to dirty filters. If you are in hot areas on the ac after a long time moisture will accumulate in the filter. Get services of professional and clean ac lines and cut completely. it solves the smell issues.
  3. Different components like PCB board, wires, fan compressor, etc in your ac unit. If you smell like burning plastic, it means one or more components in the unit are burning. So off your unit and get the services of a professional to find the solution. Another reason for this type of smell can be dust particles in the unit due to being inactive for a longer duration.
  4. The rotten ac smell is normally caused by dead rodents stuck in the unit. Birds and insects can make nests in ductwork and trapped in the devices. With time these dead animals releases also smell. When you on your ac unit discharge a foul smell in your home. Dead animals also damage components of the unit. If there ductless AC unit, lizards and other critters can go into the indoor unit and cause bad effects. So the best solution is to use a proof unit to avoid these problems and musty smells.  Get help from a technician to remove the dead animal and you can also fix this problem if you have some experience.
  5. There can be gas leakage special methyl mercaptan. Natural gas does not have a smell but in this gas methyl mercaptan used to have a certain odor. it makes sure that we can detect it to avoid any serious damage that occurs due to gas leakage. If the AC smells like skunk spray, it means gas is leaking and getting in the ductwork. When you first detect this small off-the-gas supply. then get the services of an expert to solve the issue.

Top Reasons Why an AC SMELLS MUSTY and Best Solutions

How to Prevent Air Conditioner Odors

  • Must keep the regular maintenance of AC units like filter replacement, cleaning coils, and inspection of the complete unit that will solve your smell issue and other related problems.
  • Ensure that air intakes are set at some distance from points where a small can cause smoking areas.
  • if you are cleaning your ac yourself use non-chemical cleaners to avoid chemical smells.
  • if there is a constant musty or moldy smell get services of professional duct cleaning to reduce any bacteria in ductwork.
  • The filter must be cleaned and replaced according to the guidelines of the manual. Since a dirty filter can cause musty smells.
  • if there is a stagnant water smell, make sure the drain pan is clean and the drain line is clear from any obstacles to avoid water collecting.
  • Check ductwork for leaks that can cause orders from other positions and protect them accurately.
  • if cigarette smoke is an issue make sure to smoke away from the air intake areas.
  • Use an air purifier to reduce the smell.

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