Detecting a chemical smell from your air conditioner can be concerning. Air conditioning units use various chemicals in their operation, especially refrigerants, which help produce cool air. In Singapore’s hot and humid weather, a working aircon is essential, so a potential refrigerant leak, which often smells like sweet chloroform, should be addressed promptly.
However, do keep in mind–a chemical odor can also stem from other sources, so it's important to have a professional technician inspect your unit and find the core problem.
What Causes that Chemical Smell Coming from Air Conditioners?
Reason #1 Refrigerant Leak
Refrigerant is an odorless chemical. However, manufacturers add artificial smells to alert homeowners of a potential leak, which is attributed to that chemical-like smell emitted by your air conditioner. Refrigerant leaks affect your indoor air quality and can be dangerous to your health when inhaled in high concentrations.
In most of our client cases, we often find other accompanying signs of a refrigerant leak such as warm air blowing from the unit, hissing or bubbling sounds, and increased electricity bills. It’s important to keep in mind that the air conditioner can no longer sufficiently cool the room as coolant leaks out of the unit. You will need to have this problem fixed by a professional HVAC technician.
Reason #2 Natural Gas Leak
Though Singapore’s gas supply is well-regulated, leaks can still happen, especially in older HDB flats or landed properties with gas piping. Although natural gas has no odor, manufacturers often add a chemical smell to alert homeowners of a leak. Natural gas may have gotten into your air conditioner vents, causing the chemical smell from your air conditioning unit.
If this occurs, immediately shut off your appliances, and call your gas company. Other accompanying signs of a natural gas leak are hissing sounds near gas pipes, and you might experience dizziness or nausea when indoors.
Reason #3 Ductwork Adhesives
If you’ve just installed a new aircon system or renovated your home, the chemical smell could be from the adhesives used in the ductwork. This is common in Singaporean homes that upgrade from single-split to multi-split aircon systems.
Fortunately, the smell dissipates quickly, but can still be off-putting when you first power on your air conditioning unit. To make the smell distemper faster, you should open the windows and doors of your home to let fresh air in. You can also run your aircon with the fan mode on.
Reason #4 Electrostatic Air Filter
Some aircon units in Singapore come with electrostatic filters to improve air quality. An electrostatic filter helps filter out small pieces of dust and dirt using static energy to trap the debris from getting into your air conditioning unit. They may or may not be connected to an air purifier, but they can leak ozone which would have a chemical-like smell. The chemical smell from the AC system may be due to your filter, so it is best to have our technicians handle it.
If you suspect your air filter is causing the smell, it’s best to replace the filter with a standard HEPA or carbon filter, you can also use an air purifier separately instead of an electrostatic filter.
Reason #5 Cleaning Chemical Residue
Singapore’s humid climate makes aircon servicing essential, and many homeowners opt for chemical washes to keep their units clean. However, when the chemical wash is done improperly, the cleaning chemicals can leave behind residue that is causing that smell to come from your air conditioner.
Always go for reputable services such as from Luce for your aircon needs. We have been trusted for many years by homeowners in Singapore as their preferred aircon service provider!
Reason #6 Mold or Mildew Growth
Singapore’s tropical climate creates the perfect environment for mold and mildew. If moisture accumulates inside the AC unit or ductwork, it can promote mold and mildew growth. Some molds release a chemical-like odor that resembles ammonia or strong cleaning agents.
To avoid many problems, including mold or mildew growth in the aircon, we always recommend our client clean their aircon filters monthly—especially if they live near industrial areas in Singapore.
Reason #7 Overheating Components
If internal parts like circuit boards, fan motors, or wiring overheat, they can produce a burnt plastic or chemical smell. This could be due to electrical issues, dust buildup, or restricted airflow.
To fix this issue, you should immediately turn off your aircon and call a technician to inspect the system. Do keep in mind, that continuing to use an overheating unit can cause a fire hazard.
Reason #8 Off-Gassing from New Materials
A newly installed or recently repaired AC unit may emit chemical smells due to off-gassing from plastic components, insulation, or sealants. These parts might release volatile organic compounds (VOCs).
You don’t have to worry too much, as usually, this smell will fade over time. But if you want to speed up the process of removing the smells, you can use an air purifier with a carbon filter. This will help to absorb the VOCs faster and make the chemical smell gone.
5 Tips to Prevent Air Conditioner Smells
Replace or Clean Air Filters Frequently
Singapore’s warm and humid weather means that air conditioners work harder and accumulate dust faster. A dirty air filter traps mold, bacteria, and dust, leading to unpleasant odors such as chemical smells that you might find in your aircon.
If you live in Singapore HDB or condo homes, we recommend getting your air filter cleaned once every 3 months. But if you live in landed properties near construction zones or have pets at home, you might need to clean your air filters much more frequently.
Scheduling Maintenance Regularly
Regular servicing is crucial for preventing aircon smells. In Singapore, where air conditioners are used almost daily, at least two servicing sessions per year are recommended. Your air conditioner would benefit from a checkup and maintenance of its internal components. Our technicians will spot any weak points in your cooling system, and reinforce them before they become bigger problems. This is essential to preventing leaks in the refrigerant line!
Keep the Drain Line and Coils Clean
Singapore’s high humidity can cause water buildup inside your aircon, leading to mold and mildew growth. Thus why, a clogged drain line or dirty coils can cause musty and chemical smells. We always recommend our client in Singpoare to schedule a professional chemical wash annually to clean the coils. You can also regularly clean it by flushing the drain line with warm water and mild soap every month.
Use High-Quality Materials
When replacing parts or installing a new AC unit, always opt for high-quality materials. Avoid cheap adhesives, low-quality plastic parts, and unapproved filters, which can cause unpleasant chemical odors. This doesn't mean that affordable materials are always bad, or that expensive materials are always the best.
Consult with our technician to find the best quality materials for your AC at an affordable price.
Keep AC Smell-Free with Luce Help!
A fresh-smelling air conditioner means better indoor air quality and a more comfortable home. Whether you live in an HDB, condo, or landed property, regular maintenance is key to keeping your AC odor-free.
At Luce, we offer professional cleaning, servicing, and repairs to keep your air conditioner running smoothly. Book your aircon servicing today to keep your home cool, fresh, and comfortable at all times!
Check out our article on why ac smells like rotten eggs!
