Strong Bad Odor Resembling Formaldehyde- A malfunctioned heat exchanger emits a strong and unpleasant smell that can resemble Formaldehyde.
When your furnace kicks on, you may notice a dusty odor as the air first moves through the ducts and vents. Within a few minutes, the smell should disappear. If you notice strange smells, like formaldehyde or any other strong chemical smell, it strongly indicates that your heat exchanger is cracked.
As expected the first sign of an issue could be an unusual noise. Sounds similar to a kettle boiling hence the names. This is a sign of limescale build-up that has created a “hotspot” on the heat exchanger. The noise you are hearing is steam bubbles from the water being overheated.
The smell of sulfur or rotten eggs almost always indicates an issue with gas supply. Natural gas is odorless, but suppliers treat the gas with a strong rotten egg smell to make gas leaks more detectable. If the smell is faint but does not dissipate, turn off the furnace and ventilate your home.
Chemical/Burning Plastic Furnace Smells
If you smell a strange, acrid, burning plastic smell from your furnace, you may have an electrical issue: electrical components, particularly the blower fan, cycle on and off frequently. Over time, these components can wear out and become inefficient or perform poorly.
What is formaldehyde? Formaldehyde is a colorless chemical with a strong pickle-like odor that is commonly used in many manufacturing processes. It easily becomes a gas at room temperature, which makes it part of a larger group of chemicals known as volatile organic compounds (VOCs).
The cost of replacing a heat exchanger ranges from $2,000 to $3,500. Replacing your furnace's heat exchanger would be a good route to take if your furnace is fairly new. However, it is not worth spending your money on replacing your heat exchanger when it is near the end of its life span, which is ten years or more.
Even worse, a cracked heat exchanger can be a safety hazard. For instance, if natural gas is leaking from the heat exchanger, it can create a fire or explosion hazard. It can also potentially cause carbon monoxide leakage and build-up, which can be quite dangerous.
However, a high-pitched rattling before your furnace kicks on might indicate a cracked heat exchanger, a more serious problem that may require replacement.
The only signs that you have a damaged heat exchanger are no heat during the winter, reoccurring flu-like symptoms, or a beeping carbon monoxide detector.
Furnaces have an average lifespan of around 10 years, and most exchangers tend to go out around this time. If your furnace is close to this 10-year mark, a new furnace is likely a better investment. If your furnace is relatively new, a new heat exchanger may be worth it to avoid early furnace replacement.
By using a combustion analyzer. This tool measures the efficiency of fuel burning appliances by determining the temperature and CO and oxygen levels. If the combustion analyzer detects low appliance efficiency, it means there's a combustion problem. A furnace combustion problem is a sign of a cracked heat exchanger.
If your air conditioner is giving off a smell that reminds you of dirty socks or feet, a dirty drain pan or evaporator coil could be responsible. If they aren't cleaned for a long time or get blocked, either part can attract microbial growth that can give off unpleasant odours.
The sweet smell in your car might not be your perfume or the donuts you're taking to work. It could be the heater core. If the heater core is leaking, it will blow the odor of engine coolant through the vents. Coolant smells sweet, almost musty.
A malfunctioning heat exchanger will often create an unpleasant and strong odor that smells similar to formaldehyde. Soot Build-up. White soot build-up in or around the burners of your furnace. Corrosion & Cracks.
Heat exchangers keep your home's clean air separate from the toxic air used in combustion and exchange heat between them. A failing or cracked heat exchanger can cause toxic gases–such as carbon monoxide, sulfur dioxide, and nitrogen dioxide–to be released and mixed into the air that is distributed to your home.
And remember, trying to replace a heat exchanger without professional assistance can pose potential hazards such as carbon monoxide poisoning and other safety risks.
Although a furnace will continue to heat your home even with a cracked heat exchanger, it is not safe to continue using your furnace. Using a cracked heat exchanger allows for certain toxic gases to escape from the furnace including carbon monoxide, nitrous oxide, and sulfur dioxide.
So, if your furnace is still under its labor warranty, we definitely recommend replacing just the heat exchanger since most of the repair cost will be covered under warranty. But if your furnace is no longer under the labor warranty and it's over 10 years old, you might as well just replace the furnace completely.
Because replacing a heat exchanger can take up to eight hours or longer, it represents the bulk of the cost. If your warranty is expired, and you would need to pay both parts and labor for a new heat exchanger, look further into whether a full unit replacement would be more advantageous for you.
If you're especially sensitive to scents, a bed with strong off-gassing odors may cause unwanted symptoms, such as headaches, nausea, or dizziness. Individuals with respiratory issues, such as asthma or allergies, could also experience irritation of the airway and difficulty breathing.
Some people describe this smell as similar to acetone, nail polish remover, or even chloroform. The odor may become stronger with larger leaks, but it's often subtle enough to go unnoticed. If you notice an unusual sweet or chemical-like scent near your HVAC unit or air vents, it could be a sign of a refrigerant leak.
Benzene is found in gasoline and trace amounts are found in cigarette smoke. Benzene has been banned as an ingredient in products intended for use in the home, including toys. Benzene has a sweet, aromatic, gasoline-like odor. Most individuals can begin to smell benzene in air at 1.5 to 4.7 ppm.