Exhaust fumes are easily recognizable by their pungent chemical smell, but their stench isn’t the only unpleasant thing about them.
These fumes also contain carbon monoxide, which is deadly when inhaled.
Any exhaust smell that you might be noticing around the house is one you need to get rid of right away before it becomes a threat as much as it is an unpleasant nuisance.
To do so, you’ll first have to find the source of the fumes and fix it up.
Beginning the search can leave you not knowing where to turn, but in this article, we’ll show you how to track down the smell’s source while offering four different ways to get rid of it.
Causes of Exhaust Fume Smells (and Fixes)
Before you start to hunt down the leak, beware and prepare for exposure to carbon monoxide.
Regardless of whether you know where it’s coming from or not, you should find out the levels of CO that are present. CO is always found in toxic exhaust fumes, and it can cause you to suffocate.
To start, shut off all of the appliances in the house that burn oil or gas, such as the water heater or furnace.
From there, get a carbon monoxide detector that you can place near the source of the exhaust smell.
Anything that is over 100 PPM on the readout is a dangerous level of carbon monoxide for children and adults alike.
If you have a gas mask on hand, no matter how high or low the readout is, it is recommended that you wear it just to be safe. Then detect the leading causes of exhaust fume smells that are lingering around.
1. Faulty Flue Ducts
One of the causes of the smell could be that the air can’t correctly escape and instead fills the home.
When this happens, an easy culprit to pick out is a faulty exhaust duct.
Some of the things that could be responsible for a faulty duct include:
- A flue duct that is rusted through
- Parts of a duct could have leaks or have separated
Usually, you can find out if you have these issues with your flue by the fact that you could have cleaned the duct entirely after the exhaust smells have shown up, but the smell got even stronger following cleanup.
This will happen only if the flue has an issue such as this, as a cleanup can worsen the damage and bring in more fumes in the apartment.
Below are the steps you can take to repair a broken flue duct:
Find the source
Regardless of whether separated parts are causing the smell or the flue is covered in rust, you’ll need to be sure which one is the source.
To do so, you’ll need both a strong flashlight and a trouble/drop light.
Shut the system off entirely and remove the roof cap of the chimney. Next, you need to light up the duct opening from the bottom using a flashlight as you insert a drop-light into the duct.
Be sure you can see clearly into the duct and look for any damaged, rusty, or otherwise broken parts in the duct. After you’ve located the exact damage, move on to the next step.
Remove the rust
If you traced out a rusted flue pipe or just a portion of rust somewhere that may have caused damage or a partial gap, you could fix it. Follow the three steps below to find out how.
- Using a wire brush loosen out any rust that is present.
- Use mineral spirits to remove the grease around the affected area. As you do, that oily stain that the exhaust fumes are causing will clean right up.
- Put a few coats of a galvanizing spray on all of the stubborn rust that wouldn’t lift.
- Dry it and then put the flue back in place. It will usually take about 30 minutes for it to dry. When you do it this way, you won’t have to worry about rust spreading anywhere else.
Fix the broken flu parts
Sometimes when there is a lot of dust, the flue can break, or the parts can separate. This is one of the most likely causes of exhaust fumes not properly leaving the space.
To fix it, seal off the broken areas or leaks after you have dealt with the rust in step two. You can patch the leaks using a moldable, small sealant if the cracks are small.
You might need to add insulation around the damaged area if they are more extensive. Wrapping the area using roof tape could work well to serve as insulation for the flue duct.
If, in the end, you find that the damage is beyond repair, you can simply replace the flue with a brand new one.
2. Partially Blocked Airflow
Any interruption in the HVAC system can cause it to malfunction, and in this case, it can start from the reverse directing of these fumes back into your apartment home.
Besides issues with the actual flue inhibiting the air’s ability to flow out, it can also be the fault of outside elements locking the airflow from the vent.
Some situations that could cause this include:
- A bird’s nest or similar blockage may have entered the furnace through the duct cap on the roof.
- If anything is hanging in front of it that way, it could direct the exhaust fumes right back into the flue.
- There could a blockage in the air inlet of the HVAC system you’ve installed, including the furnace, air conditioning, heater, or water heater by a bird’s nest, insects, and something else.
This will cause weak combustion and only partially blow out the burned gas throughout the rest of the system.
The easiest fix is to remove whatever is locking the furnace crown or vents. This can mean a bird’s nest, debris, dust, bugs, and other contaminants.
Bird/Birds Nest Blockage
If the bird’s nest or an alive bird is what’s causing the problem, be careful if you try to extract them.
Wear gloves as you lead the bird out or pick up the nest. There is no other choice outside of relocating the nest.
Blockage by Dust and Debris
If dust particles are clogging up the exhaust or inlet, you’ll find that this is common with a higher-efficiency furnace that hasn’t been cleaned for some time.
If any construction on the home took place around it, it is likely that there is construction debris clogging up the ducts.
Fortunately, cleaning out the dust from the inlet is an easy process. Simply follow the steps below:
- Find the exit point of the exhaust and intake pipes.
- Using a screwdriver, open up the vent pipe.
- Pull out any large dirt and debris from it.
- Use a clean, soft cloth or brush to remove the stickier debris and dirt.
- Use an air duct cleaning vacuum to clean out the whole vent.
- Look for any other blockages using a wire hanger that you shape into a shepherd’s crook.
- Use the screwdriver to close the pipe back up.
3- Garage Fumes Inside the House
A study done by Health Canada noticed that homes that have an attached garage could bring with them a significant amount of a gasoline pollutant known as benzene.
It can be difficult to prevent the fumes from making it into the house through cracks, leaks, and gaps.
If you follow the steps below, you can operate with relative certainty that the gap is closed up.
Seal Garage Cracks on the Ceiling
Take a thorough look around the garage to find any kind of gaps, leaks, cracks, or holes in the garage to the home. This includes looking between non-air-tight doors and the ceiling edges.
If you find any gaps, use putty, caulk, spray foam, weather-stripping, and other materials to seal up the holes.
Finish the Drywall and Ceiling Wall
It is common for any new home to have drywall and ceilings with unfinished joints.
These tiny cracks offer plenty of room for exhaust fumes to move through and need to be taken care of.
To remedy this, take an in-depth look at the joints in the drywall to ensure they’re adequately sealed with compound and tape. The paint and primer will also need to be checked for leaks as well.
Burn Gas or Oil with Care
Exhaust fumes come from a gas or oil burner used in the garage.
In order to prevent the smell and fumes from getting into the house, it’s a good idea to run any engines or power tools as close as you can to the window to help ventilate the space.
Otherwise, use a fan or a separate vent to move it out of the space.
4- From the Neighborhood
Though the possibility is slight, there’s a chance that the fumes are coming from the surrounding areas.
You can check for a closely placed exhaust vent near the ground-level wall.
If your neighbor has a heating system or furnace that is large enough, there is a chance it could get through the air inlets and cause the smell.
The closer you live to your neighbors, the more likely this could be a problem.
You and your neighbor may need to work together to set your two vents, including your inlet and your neighbor’s exhaust, at a distance from each other.
You can also ask them to add ducting atop the exhaust in order to move it towards the roofs instead of your house, since moving your inlet vents is a trickier and more time-consuming process.
If you get rid of the exhaust smell and want to make sure it never returns, there are some steps you can take:
Keep your ventilation system clean
Residential air ducts are often full of hair, dirt, spider webs, foliage, and other debris. Be sure you clean them regularly, as often as once a month, and you can prevent these blockages.
This will also make your HVAC system run more efficiently, saving you money while also eliminating the risk of exhaust fumes getting into the home.
You can use tools such as a vacuum cleaner, wire brush, cleaning brush, broom, or other such tools to clean it out. If you use a vacuum, be sure it has a long hose that can get deep inside the vents.
This will help remove the mildew and mold buildup inside the duct. You should also be cleaning the grills regularly.
Space Out the Exhaust and Inlet
To prevent the exhaust from feeding right into the inlet, ensure they aren’t too close.
The inlet can quickly suck up what comes out of the vent, even though one points up and one points down. Try to keep them at least five feet apart and keep the area free from clutter.
Keep Your Air Filter Maintained
Alongside the furnace filter, you’ll also want to clean and maintain your air filter once a month and check for any broken pieces.
Usually, because of poorly fitting filter slots or overuse, air filters can bend or otherwise displace.
If it is positioned this way, it won’t be able to keep the exhaust fumes out. Check for damaged or ill-fitting air filters regularly.
Why Does My Furnace Smell Like Diesel Exhaust?
If you smell diesel exhaust coming from your furnace, it could be due to a clogged chimney or a faulty burner.
Either way, it’s important to have the problem diagnosed and repaired by a qualified HVAC technician to prevent any potential safety hazards.
A clogged chimney is one possible reason why you may smell diesel exhaust coming from your furnace.
When a chimney becomes clogged, it can cause hot smoke to come out of the furnace and fill the room with an unpleasant smell.
To fix this problem, you’ll need to have the chimney cleaned out by a professional.
Another possible reason for the diesel smell is a faulty burner.
If the burner isn’t adjusted correctly, it can cause smoke and fumes to escape from the furnace. A qualified HVAC technician can adjust the burner and eliminate the Diesel smell.
If you notice a foul exhaust fume smell, you must take immediate action; you don’t want the carbon monoxide from the fumes filling up your home and causing you to suffocate.
In this article, we provided four of the most common causes of exhaust fumes getting into your house.
We also offered steps you can take to fix the leak regardless of its source. Finally, we left tips on how to prevent it from coming back.
Meen Smith is a nurse by profession who loves writing online, spending time with her family and caring for the elderly. She has already worked as an associate editor on various moms, babies, home appliances, kitchen, and healthy living blogs. In her spare time, she also enjoys drawing, reading/writing kindle eBooks and improving her skills a bit.