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By November 22, 2022November 29th, 2022No Comments

How do you know if you need air duct mold removal? Do you know how to hire a reputable company to clean your ducts? Is mold really that dangerous? Come learn all you need to know.


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The main reason your HVAC system gets dirty in the first place is through neglect. Forgetting to change air filters, using poor filters, having gaps in filters, or no filter at all(!), could affect how clean the system is. Leaking ducts (especially in crawl spaces under homes) can also be culprits for dirt, dust, insects, and even animal droppings.

A dirty nearby environment can also affect your HVAC system negatively. New construction, factories, and nearby highways can increase pollution outside your home or workspace. Dirty outside air dramatically increases the amount of pollution inside a building.


Having mold in your HVAC system is much more common than you might think. In fact, when we check an HVAC system during a mold or indoor air quality inspection, we find mold more often than not.

Most of the time the mold is located inside the air handler on the coil. There are two simple reasons for this:

  1. Water is present on the coil when the air conditioner is running. The water is deposited as moisture is removed from the air during cooling.
  2. Air filters inadequately prevent dust (aka ‘mold candy’) from being deposited on the coil, usually because they are of poor quality, do not fit properly, or are missing altogether.

Once mold has begun growing inside the air handler, mold spores are blown into the home’s living space every time the heat or air conditioner runs. This compromises indoor air quality and can cause additional mold growth inside the ductwork and the home.


According to the EPA, there are 3 main reasons you might want to have your ducts cleaned:

  1. Ducts are clogged with dust or debris and the particles are being released into your home (see image above)
  2. Ducts are infested with rodents or insects
  3. There is substantial mold growth inside your heating and cooling system.3
  4. Purchasing a home is another time when duct cleaning may be needed. If previous owners had pets or smoked, it is more likely that ducts could be clogged or need cleaning.

If your HVAC (Heating, Ventilation, and Air Conditioning) system is in a crawl space, it is also more likely to be prone to leaks and mold growth. For more information see our post: HVAC System in Your Crawl Space? You May Be Breathing Dirty Air.


Yes! Indoor air can retain chemicals, volatile organic compounds (VOC’s), mold spores, pollen, microbial volatile organic compounds (MVOC’s), toxins, bacteria, viruses, and other irritants more easily than outdoor air. All of these things can make you feel sick and some can even cause disease.

Infectious bacteria and viruses can cause disease. Mold can cause mental and physical health problems including: allergy sensitization, shortness of breath, allergic reactions, asthma attacks, and mental health problems including: disordered brain function, changes in balance, slower blink reflexes, slower reaction times, color discrimination problems, and depression.


The answer is maybe. If your system is dirty, through neglect, leaking ducts, mold growth, or poor air filtration it could help significantly! However, people eager and willing to sell you ‘duct cleaning services’ for a gimmick price are all too many! Before you rush to get your ducts cleaned, keep reading! We tell you all about all the tricks, and how to really get your money’s worth.


Does your home have a musty odor even after cleaning? Can you see visible mold growth near vents, air returns, or on filters? If you can see it or smell it (musty wet dog or gym bag types of smells), you may have mold in your air ducts.

In addition, if you are constantly ill with allergy symptoms, you may also want to have ducts cleaned. Even if mold is not present, allergens such as dust, pet dander, smoke, VOC’s (volatile organic compounds), microbial volatile organic compounds (MVOC’s), and more can build up in your HVAC system. These allergens need to be removed to improve your health. To learn more about allergens in your home check out our post: How Your Home Can Affect Your Allergies.

If you have mold inside your HVAC air handler, it’s best to have a professional clean the coil, fan, and possibly the ductwork. This is a service that most HVAC and mechanical contractors offer. Be sure to look at the coil yourself before they close the unit up, or ask for pictures to verify that the contractor has done a thorough job.


Air duct cleaning is not a DIY project. Special equipment is needed to remove dust, dirt, mold and debris. You really do need to choose a professional for this job. How can you choose the right contractor? What questions should you ask them before hiring them? What kind of advertising should you expect?

  • Duct Cleaning Special, only $39.99!
  • Duct cleaning 84% off!
  • $290 worth of services for only $29.00!

What do these three statements have in common? They are all gimmicks to convince you that these companies will really give you an amazing deal. But y’all, when it’s too good to be true, it probably is. There are a lot of people out there who will try to take advantage of you with duct cleaning scams. They claim you get all these ‘services,’ but what they really do is rip you off.


Don’t let this happen to you! Here’s what you should know when hiring a company to clean your ducts.

Top 3 Duct Cleaning Scams

1.Blow and Go – The technician comes in and looks around, gets surface dust and dirt, and then leaves. They typically have many appointments in one day and don’t spend enough time truly trying to clean the ducts. They may not even remove parts to get to the interior of the system.

2.Bait and Switch – That $39.99 cleaning turns into $700 amazingly fast.7,8 They bait you with the cheap price, and then up-sell, or even charge for additional work you didn’t agree to have performed! Then, their work is still low quality.

According to the EPA, duct cleaning “services typically – but not always – range in cost from $450 to $1,000 per heating and cooling system, depending on: the services offered, the size of the system to be cleaned, system accessibility, climatic region, and level of contamination.”4 Any provider that offers a ‘$39.99 duct cleaning special,’ isn’t offering a full service cleaning. There are many scam artists out there. There are also unscrupulous companies who plan to ‘add on’ additional services whether you agree to them or not.

3.Mold Inspection – Scammers prey on your fears, use a cheap coupon or add to get their foot in the door. Then, they tell you you have mold…even if you don’t!

Here’s where we can help. If mold has been ‘found’ by a contractor, put a hold on the job, and get a second opinionHere at Branch Environmental, we are experts at mold remediation and can tell you for sure if you have a problem or not. Call us or schedule an inspection today!

Especially if you don’t live in our service area, check out our post: How to Choose the ‘Best Mold Removal Company Near Me.’ Use our guide to help you choose the right company for your needs.

How to Protect Yourself from Scams

  1. Do your homework – Know as much as you can about the company before hiring them.
  2. Avoid advertisements or specials that advertise ‘whole house cleaning specials’ for less than $100. If it seems too good to be true, it probably is.
  3. Request a system inspection before agreeing to the cleaning.
  4. Ask for proof of insurance. A reputable company should be able to show you instant proof of important documents.
  5. Hire a professional. Does the company have a good reputation? Are they transparent in what they are selling? Can they tell you more about the process of cleaning before you agree to have it done?
  6. We’re Here When You Need Us. We routinely inspect HVAC systems, and can tell you for sure if you have mold. If you do have mold, you want it to be removed safely. Call Branch Environmental. We’re experts not only at mold removal, but at determining and remediating the underlying causes.


Now that you have a clean HVAC system, how do you keep it that way? You cannot remove all mold spores from the air, or keep the coil completely dry during the summer.

The best way to prevent mold from growing is to keep dust out!

To prevent dust from coming into contact with the coil, choose a high quality, appropriately sized air filter that is changedor if it is washable, cleaned on a regular basis.

Of course, remember to change the filter at least every 3 months, or to wash and replace washable filters every month. When choosing a washable filter, remember that it must be completely dry before putting it back into the system. For washable filters, it’s better to have two, one to wash, and one to use.

All Air Filters Are NOT Created Equal!

All air filters are not created equal. To begin, determine the size of the filter needed. It sounds like a no brainer, but people use the wrong sized filters all the time. Incorrectly sized filters will not filter the air properly causing dirty vents and dirty air.

What size air filter do I need?

Especially if you are suspicious that the air filter is not the correct size, you should measure the air intake.

  1. Start by turning off the unit. You don’t want air blowing through the system without a filter! (Not having a filter is a great way to increase dust aka ‘mold candy.’)
  2. Next, using a measuring tape, measure the length, width, and depth of the inside edge of the filter’s slot frame.
  3. Round down to the nearest whole number. The actual filter should be ¼” to ½” smaller than the inside of the frame.

Of course if you think the filter is the correct size, measure the filter to get the correct size to replace it. It can be tricky to measure the inside of the frame correctly. Be sure to measure carefully.

What kind of filter do I need?

Next, determine what MERV values your HVAC system can handle. MERV stands for minimum efficiency reporting value, or how efficient your filter is at removing dust, dirt, smoke, pollen, carpet fibers, pet hair and dander, mold, bacteria, and even viruses. The higher the MERV value, the more effective it is at removing all of those nasty things from your air.

Not all HVAC systems are created equally either. Some systems can handle using a filter with a high MERV value and others cannotBe sure to find out what MERV ratings your system can handle before purchasing one that is not designed for your system.

Finally, once you know what size and MERV value are best, make your purchase with confidence! Of course, remember to change the filter at least every 3 months, or to wash and replace washable filters every month.


Regular maintenance keeps your HVAC system cleaner and healthier for everyone. Mold prevention includes:

  • Changing or cleaning filters regularly
  • Using the correct size and MERV rated filter
  • Keeping vents clean and in good working order
  • Checking ductwork on a regular basis

These 4 steps can prevent many HVAC problems. Duct cleaning can improve your health, especially if you have mold, allergies to dust or pet dander, or have specific problems such as: insect or rodent infestations.

Avoid scams by doing your homework, and request important documents, such as insurance, before technicians arrive. Don’t fall for cheap coupons or gimmicks. If they say you have mold, get a second opinion.

Better yet call us, and we can tell you for sure. We believe that no one should live or work in a building that makes them sick. We will treat your home like it’s our own. From hidden mold sources to major contaminants, we can identify exactly what is going on in your home and rid it of environmental toxins, often for good.

Branch Environmental – Because nobody should live or work in a building that makes them sick.


Join Thousands Of Other Customers Who Have Already Eliminated Toxins From Their Homes, And Their Lives.