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Maximize Your Commercial Air Duct Cleaning Productivity

 

 

Productivity is the key to maximizing your profits on commercial air duct cleaning projects because 95% of your cost is for labor.  One of the best ways to maximize your productivity is to have the right equipment and tools for these types of projects.  Let’s look at the equipment and tools that can help you maximize your productivity on these large and complex HVAC systems: 

Vacuum Collection Systems: 

• Electric portable systems let you position the collector where you need it to minimize the number of hook-ups.
• Systems that deliver better performance (suction) means you can clean longer duct runs with one hook-up. 
• Systems with cleanable pre-filters eliminate the cost associated with replacing pleated bag filters.
• Systems with high capacity HEPA filters, which last longer than standard HEPA filters, save you time and money.
• Systems with larger collection capacity mean fewer stops to clean them out maximizing your up-time.

Cleaning Smaller Ductwork: Typically 6”-16” in size.

• Flexible cable brush systems work well in this size ductwork when there are turns and drops. Plus the brushing action gives you the best cleaning results.
• Solid core cable brush systems work well in this size ductwork when there are straight runs.  Plus the brushing action gives you the best cleaning results.
• Whip systems work well in this size of ductwork and they don’t require a final air wash which saves time.

Medium Size Ductwork: Typically 12” to 22” high and 12” to 48” wide.

• Brushing systems (pneumatic or electric) with different size brushes and the ability to center the brush height wise in the duct (so it is hitting both the top and bottom of the duct) will give you maximum cleaning effectiveness and productivity.
• The longer the reach of these brushing systems the fewer the access opening you need.  Gone are the days of cutting access openings every 10’ and reaching in and contact vacuuming.
• Brushing systems with cameras and robotic brushing systems let the operator see the brushing operating to maximize cleaning quality and productivity.

Cleaning Large Ductwork:  Typically larger than 24” x 24”.

• Putting a person inside the ductwork and cleaning by contact vacuuming or with a blow gun and shop brush gives good results and productivity (because the technician is right there and can see everything).
• If crawling the ductwork is not practical or safe brushing systems or robotic systems with large brushes (24” and up), centering devices, and long reach capability will give you the best productivity.

Cleaning Insulated Ductwork or Duct Board: Assuming the insulation is not friable and in good enough condition to clean.

• Brushing systems with nylon brushes that you can spin at a slower rpm does a good job of cleaning medium size insulated ductwork without damaging the insulation.
• Contact vacuuming is also a good option on large insulated ductwork.
• After cleaning, coating is highly recommended because it locks down any remaining loose fibers and give you a more durable surface that is more resistant to air erosion and moisture.  This extends the life of that ductwork.
• Cleaning and coating is much cheaper than replacing the ductwork.

 Air Handler/Plenum:

• Cleaning by contact vacuuming or cleaning with a blow gun and shop brush gives good results (because the technician is right there and can see everything) and maximizes your productivity.

No one tool can magically make you more productive in every situation but a tool kit with the right equipment and tools will give you what you need to maximize your cleaning quality (for greater customer satisfaction) and productivity (for greater profits).

 

Link to cleaning tools         Link to vacuum collection systems

Electric Vacuum Collection System - Check List

Electric portable vacuum collection systems give you maximum versatility to clean the HVAC systems in the widest types of buildings.  This gives you the largest possible market for you to service and maximizes your earning potential.  Residential electric portable vacuum collection systems let you clean homes, apartments, condos, marine and light commercial buildings.  Commercial electric portable vacuum collection systems let you clean all types of commercial projects like hospitals, schools, office buildings, industrial buildings etc.  

If you are thinking about electric portable vacuum collection systems take a look at the following check list of features you should consider and why.  

1. Portability is important because you want to help your technicians be successful.  If a unit is easy to move in/out of the building or home and go up/downs stairs, set up and take down will be easier.  Your technicians will be happier and more productive.   What determines portability?  Here is what to look at:

• Weight of the unit.  A lighter unit is easier to move up/down stairs than a heavier unit.  If you have one person crews you need a vacuum collection systems that one person can handle.
• Number of sections.  A single section unit is easier to move than a multiple section unit.
• Height of the unit:  If a unit is over 5’ high it can be harder to move up/down stairs. 

2. Performance is importance because is a major factor in determining your productivity.  By performance we mean suction and the more suction the better.  How do you know since there is no accepted industry standard?  You shouldn’t use “free air” cfm because that is just a measurement of a fan that is not in a cabinet and without any filters in place.  Here is what to look at:

• Size and number of the fans.
• Size and number of motors.
• If available, measured cfm of unit with all filters in place.  

3. Electrical requirements are important so you know a unit will work in widest variety of homes/buildings.    To maximize your potential market you want your electric vacuum collector to be able to work in the widest variety of homes/buildings.  This means your unit must be able to operate on the lowest electrical service that is normally found. 

• For USA market, make sure your unit will operate on 120volt/60Hz/15amp circuits from start-up to full load.
• For overseas markets, make sure your unit will operate on 220volt/50Hz or 220volt/60Hz circuits whichever is required.  

4. Owning and operating cost is important because together they make up the total cost you will pay over the life of the unit.   First cost is important but is only part of your total cost.  The other cost factor is operating cost which is your filter replacement cost.  Over a 5-10 year life span your filter replacement cost can be more than your first cost.  Here is what to look at:

• First cost (your purchase price).
• Ask for a 5 year filter replacement (pre-filters and HEPA filters) cost estimate.
• Ask if any of the pre-filters are cleanable.
• Ask if the HEPA filter is standard or high capacity.  High capacity HEPA’s will last longer before the need to be changed.  

5. Quality of unit is important to help insure long life.  The longer you can own and use an electric portable vacuum collection system the more value it gives you.  It’s obvious that it’s to your benefit to take good care of your equipment but there some things that are outside your direct control.  Here is what to look for:

• Warranty (length and what it covers).
• Ask if there is any performance guarantee.
• Ask for references of past customers so you can ask about their experiences.   

If you analysis and compare these 5 features you will find an electric vacuum collection system that best fits your needs and requirements.   For a more in-depth look at this topic click on the following link:

 

Choosing the right tools for applying coatings in HVAC Systems

Applying coatings in HVAC systems is becoming more common and accepted in the industry.  In many cases coating is called for in the specifications on fire restoration projects, mold restoration projects and projects that have internally lined ductwork or ductboard. 

Choosing the right tools to apply coatings in HVAC systems can go a long way to help maximize coating productivity and quality.  Unfortunately, no one tool can do everything so let’s look at the tools normally required to apply coatings in HVAC systems.

1.   Coatings.  A coating is not an application tool but it does have an affect what tools you do use.   There are many coatings on the market with a wide range of viscosity and fiber content.  This can dictate what size of airless sprayer you use.

2.   Application Tools.

Commercial airless sprayers are the primary application tool for applying coatings in HVAC systems.  They work very well when applying coatings in air handlers and large duct work that you can get inside.  You simply spray like you were paint a wall in your house. They do not work well in smaller ductwork (ductwork you cannot get inside) because you would need to cut an access opening every 5-10 feet so you can reach inside with the handle held spray gun (sometimes with extension wands) and spray.  This is very time consuming and not very productive.

When selecting and airless sprayer (renting or buying) you need a commercial unit not a typical home owner sprayer.  Your local commercial painting contractor supply house typically would have the type and size sprayer you need applying coating in HVAC systems.  The coating you are applying will dictate the size of airless sprayer you need.  Thicker coatings will require a larger/more powerful airless sprayer than thinner coatings.  Average viscosity coatings need an airless sprayer that has 1.4 hp motor and a .7 gpm pump while a thicker viscosity coating will need an airless spray that has 2.0 hp motor and a .95 gpm pump.  An undersized airless sprayer is one of the most common problems on coating projects. 

Cart spray systems are used with an airless sprayer to apply coatings in smaller HVAC ductwork.  The liquid line from the airless sprayer is connected to the back of the cart spray system.  The airless sprayer pump then pumps the coating through the liquid line, through the cart spray system and out the spray nozzle(s) to coat the interior of the ductwork.  You typically place the cart spray system at the far end of the duct you want to coat and pull back on the push/pull rods or liquid line as you spray.  Some systems use 360 degree spray nozzles.  These systems work will for ductwork under 20” high and some systems have rotating or spinning spray nozzles.  These systems work well for ductwork from 20” to 36” high.  Cart spray systems range in price from $400 to $1,800.

Robotic spray systems are used with an airless sprayer to apply coatings in smaller HVAC ductwork.  The liquid line from the airless sprayer is connected to the back of the robotic vehicle.  The airless sprayer pump then pumps the coating through the liquid line, through the robotic spray system and out the spray nozzle(s) to coat the interior of the ductwork.  You typically drive the robotic spray system to the far end of the duct you want to coat and drive in reverse as you spray.  Some systems use 360 degree spray nozzles (for smaller ductwork) and some use a rotating or spinning spray nozzles for medium to large ductwork).   Robotic spray systems range in price from $6,200 and up.

If you want more information on coating HVAC systems we offer a link to our Introduction to Coating HVAC Systems Guidelines and our Super Cart Spray System Family.  Also, please feel free to call me at 800-597-3955 or 952-808-1619 if you have any questions about coatings, airless sprayers and cart/robotic spray systems. 

Grow Your Residential Air Duct Cleaning Business

As you think about ways to grow your business your first step is to take a minute and evaluate your current business plan and practices.  You need to know where you are before you can move forward and grow. Ask yourself:  What can I do better?  How can I better serve my customers?  How can my customers better serve my goals?  What new or different growth options are available for me?

Here are four ideas that can help you grow your business:

1. Get more referrals from your existing customers.
2. Expand your marketing to reach a larger audience.
3. Network with other trades.
4. Expand your service offering.

1. Get more referrals from your existing customers: Your existing customers are one of your biggest assets. You have already won their business and trust.  The challenge is to take this trust and make it work for you in the form of getting more referrals!   

• First, you make it so easy for them they can’t help but do it by doing a great job every time.  Many people do good work and there is nothing wrong with good work.  You need to aim higher so your customers think the world of you and the service you provided.
• Second, create a customer referral reward program that is easy and rewarding for both your customer and you.

2.  Expand your marketing to reach a larger audience:  Look at the geographic area you currently serve.  Can you expand it?  Are there areas that offer greater potential than others?  Pick out a new area and then market to them.  You can:

• Offer something these new potential customers would like.
• Distribute your direct mail piece to that new area.
• Use direct mail packs that go to the zip codes of that new area
• Put door hanger flyer on the homes in the new area.
• Use radio and local television, they generally covers a large geographic area.

 Try different things but keep track of what works best so you can use that strategy again.

3.   Network with other trades: You can increase your business by networking with other trades that can use you as a subcontractor to provide their air duct cleaning services.  These trades can include:

• HVAC contractors
• Fire Restoration contractors
• Water/Mold Restoration contractors
• Carpet cleaners
• Chimney sweeps
• Home inspectors
• Janitorial service contractors (that service apartments and condos)

You first have to sell these other trades on your ability and the quality of your work.  Take them to one of your jobs or give the owner a free HVAC system cleaning.  Once they agree to use you and you have negotiated their compensation, you need to provide quality and timely service.  If you do they should continue using you and help you to grow your business.

4.  Expand your service offering: Look at your current service offering.  Are there things you can add to make you more valuable to your customers?  Are there services you could add that would set you apart from your competition?   Listed below is a list of some things you may want to consider adding:

• Coil cleaning
• Furnace cleaning
• Dryer vent cleaning
• Filter upgrades
• Carbon monoxide testing
• Duct leakage testing and sealing
• UV lights

Expanding your service offering will enable you to better serve your customers (which helps generate more referrals), increase your revenues per job and help set you apart from your competition. 

If you have questions or want to discuss these four ideas please contact Peter Haugen at 800-597-3955, 952-808-1619, or phaugen@vacsysint.com.    You can also read a longer article on this same subject by clicking this link.

Is Leasing A Good Option For Air Duct Cleaning Contractors?

Air duct cleaning contractors require equipment in order to operate their business.  Usually a contractor will use internally generated cash flow, operating credit lines from their bank, bank loans, credit cards, or leasing as the funding source for their air duct cleaning equipment purchases.  In today’s economy with the tight banking credit, leasing can be a very attractive funding source for equipment purchasing.  Why?  Because leasing offers some unique advantages like:

• Leasing is pretty easy:
  • You typically complete a 1 or 2 page application.
  • You can normally get approved in a day.
• Leasing is flexible:
  • You determine the length of your lease.  Typically they are in the 3 to 5 year time frame.
  • You can schedule in skip payments if you have a historically slow period or delay payments until the equipment begins to help you generate revenues.
  • In most cases you can pay off the lease early if you want to.
• Leasing preserves your cash:
  • It does not affect your bank line of credit.
  • No large down payment is required like with a bank loan.
  • In some cases the lease payment is tax deductible.
• In most cases the payment from one air duct cleaning project will be enough to make your monthly lease payment.

In addition to offering a wide selection of “field-proven” air duct cleaning products we offer leasing as one of our purchasing options.   If you have any questions about leasing or equipment please contact Peter Haugen at 800-597-3955 or 952-808-1619.   

What Type of Vacuum Collection System is Right for You?

Your vacuum collection systems is the heart of you HVAC systems cleaning operation so deciding on what type of systems to use is very important.  There are lots of different models available but the basic types of systems include:

• Electric portables systems
• Gas portables systems
• Gas truck/trailer mounts systems
• Big truck systems

Within each of these types you have many choices from a wide range of manufacturers.  So how do you decide on which type is best for you?  You need to examine a variety of variables and weigh their importance to you.  These variables can include:

• First cost
• Operating & maintenance cost
• Performance (suction)
• Portability
• Productivity
• Types of buildings you want to clean
• Image
• Quality
• Warranty
• Etc.

If you want to do residential and light commercial (one story) projects you can use any of the four types.  If you want to clean residential, apartment, condos and light commercial (multiple stories) projects you would look at electric portable vacuum collection systems because you can’t really use a gas unit on multi story buildings.  If you want to do commercial projects you would look at electrical portable systems because many of these building are multiple stories.  But you typically would not want to use your residential unit but a larger electric portable with more performance so you can be more productive.   Let’s look at each of the four types of vacuum collection systems and see there good characteristics (+) and the characteristics that limit their use (-).

Portable Electric Systems for Residential:
+ Good performance (suction)
- Zoning normally required
+ Excellent portability
+ Lowest first cost
+ Lowest operating cost
+ Lowest maintenance cost
+ Can do residential and one story light commercial
+ Can do apartments and condos

Portable Electric Systems for Commercial
+ Good performance (suction)
- Zoning normally required
+Good portability
+ Lowest first cost
+ Lowest operating cost
+ Lowest maintenance cost
+ Can do residential and one story light commercial
+ Can do apartments and condos
+ Can do all types of commercial

 

Portable Gas Systems:
+ Very good performance (suction)
+ Zoning not normally required
+ Adequate portability
- Medium first cost
- High operating cost (gas)
+ Low maintenance cost
+ Can do residential and one story light commercial
+ Can do certain 1-2 stories commercial
- Cannot do most multi story commercial
- Cannot do apartments and condos

Trailer/Truck Mounted Systems (gas):
+ Very good performance (suction)
+ No zoning required
+ Adequate portability
- High first cost
- High operating cost (gas)
- Medium maintenance cost
+ Can do residential and one story light commercial
+ Can do certain 1-2 stories commercial
- Cannot do most multi story commercial
- Cannot do apartments and condos

 

Truck Systems (gas):
+ Best performance (suction)
+ No zoning required 
+ Adequate portability
+ Best visual impact
- Highest first cost
- Highest operating cost (gas)
- Highest maintenance cost
+ Can do residential and one story light commercial
+ Can do certain 1-2 stories commercial
- Cannot do most multi story commercial
- Cannot do apartments and condos

By determining what types of building you want o work on and what variables are most important to you can determine what type of vacuum collection system best fits your needs.  Then you should contact the various manufacturers of that type to see what units they have to offer you.

What You Need To Know About the NADCA Air Duct Cleaning Vacuum Test

 

  

The requirement for the NADCA Vacuum Test is appearing more and more frequently in cleaning specifications for commercial air duct cleaning projects.  This article will help explain what it is, how you do it, what equipment you need and where to get that equipment. 

What is the NADCA Vacuum Test?

The NADCA Vacuum Test is one of three methods to verify your cleaning results. 

• Method 1 is a "Visual Inspection" where you and your customer agree that a surface is clean.
• Method 2 is a "Surface Comparison Test" where you contact vacuum a surface that has already been cleaned to see if there is a difference.  If you can see a difference then the surface is not clean.  If you cannot see a difference then the surface is clean and you have passed the Surface Comparison Test.
• Method 3 is the "Vacuum Test" is a scientific approach where you use a vacuum cassette with filter media that is attached to a calibrated air pump.  You then pass the open face of the cassette over the opening in a template.  The cassette collects any remaining particulate on the surface.  You then send the cassette to an IAQ Lab for analysis.  The lab basically weights the cassette to determine how much particulate was picked up.  This particulate must not exceed .75mg/100cm².  If it does, you have failed the test.

The exact procedures for all three of these cleanliness verification methods and equipment specifications are detailed in NADCA’s cleaning specification call Assessment, Cleaning and Restoration of HVAC Systems - ACR 2006 on pages 24 and 25.  Contact NADCA at www.nadca.com or call 202-737-2926.

You Will Need the Following Items:

• A copy of ACR 2006 (from NADCA).
• The plastic template (from NADCA).
• An air sampling air pump that can be calibrated to an accuracy of + and – 5% at 15 liter per minute of air flow (can be found at www.zefon.com: Z-lite – IAQ Pump, costs $169.00).
• Filter media within the vacuum cassette must be 37mm mixed cellulose ester (MCE) matched weight filters (0.8 micrometer pore size preloaded in a three-piece cassette) can be found at www.zefon.com: cassette # 7M93M, costs $200.00 for 50 cassettes).
• You will need to find a Lab to send the cassettes too.  If you type in “air testing labs” in any search engine like Google, Bing etc. you will see a list of labs that you can contact to find out the mailing procedures, cost, turnaround time and type of report you get. 

If you have any questions please call me at 800-597-3955 or 952-808-1619.  Go to this link if you are looking for air duct cleaning equipment and tools to help you pass these cleaning verification tests.

What Level of Air Duct Cleaning Is Right For You?

You will encounter many different types of ductwork (supply, return, exhaust, metal, flex, lined, duct board, etc.) as you offer your air duct cleaning services.  You have a choice of many different types of air duct cleaning tools to use to clean this wide variety of ductwork.  But since no one cleaning tool can clean every type of ductwork how do you decide?  A good approach is to ask yourself what level of cleaning results do you want achieve?  

Let’s look at the three widely accepted levels of cleaning the various cleaning tools deliver:

Level 3 - Air Washing:  Air washing is the use of high-pressure air that comes from the air compressor through an air hose to an air nozzle. This air nozzle delivers streams of high-pressure air, which dislodges the accumulated dirt and debris found in the duct.   Common air washing tools include:

• Forward skipper lines
• Reverse skipper lines
• Blow guns

Level 2 – Air Whipping:  Air whipping is the combination of air washing (high-pressure air) with some agitation from the whip(s).  The high pressure of the air and whipping action dislodge the accumulated dirt and debris found in the duct. Air whips achieve a higher level of cleaning than air washing because they add some agitation.  Common air whipping tools include:

• Single whip systems
• Tri whip systems
• Eight whip systems

Level 1 – Brushing: Brushing (both manual and powered systems) makes physical contact with the interior surface of the duct.  This brushing action effectively dislodges the accumulated dirt and debris found in the ductwork.  Bushing achieves a higher level of cleaning than both air washing and air whipping because it makes more contact with the interior of the ductworks. Common brushing tools include:

• Manual brush systems
• Drill driven flexible cable systems
• Drill driven solid core cable systems
• Pneumatic driven brushing systems
• Electric long reach cable brush systems
• Electric robotic systems with brushing capability  

Level 1 – Contact vacuuming: Contact vacuuming makes physical contact with the interior surface of the duct.  This contact vacuuming action effectively dislodges the accumulated dirt and debris found in the ductwork. Contact vacuuming achieves a higher level of cleaning than both air washing and air whips because it makes more contact with the interior of the ductwork.   Common contact vacuuming tools include:

• Wet/dry HEPA filtered vacuums

Most air duct cleaning contractors are trying to achieve a “visibly clean” standard.  You can achieve the visibly clean standard with all three levels of cleaning tools depending on the type of ductwork and the amount/condition of the accumulated dirt & debris. 

What is your favorite cleaning tool and why?

If you have any questions or want additional information on cleaning tools and levels of cleaning see our - Selecting the right cleaning tool for the job guide.  Or call me at 800-597-3955 or 952-808-1619.

What is "free air" cfm?

“Free Air” cfm is a measure of airflow.  CFM means cubic feet per minute.  Many manufacturers of electric portable vacuum collection systems refer to “free air” cfm in their marketing materials when they are talking about the performance (or suction) of their vacuum collection systems.  

A “free air” cfm number is not the actual cfm of a vacuum collection system on the jobsite.  Let’s examine why this is true.

Let’s start by looking at the fans themselves.  These backwards inclined airfoil fans are typically referred to by their “free air” cfm rating number which is typically the highest cfm number on the fans fan curve,  In our industry we typically use the following three fan sizes:

• The 11” diameter fan is called a 2,500 “free air” cfm fan
• The 12.3” diameter fan is called a 3,500 “free air” cfm fan
• The 14” diameter fan is called a 5,000 “free air” cfm fan

The fan manufacturers test these fans in a lab setting by spinning them at 3,500 rpm’s and then plotting the performance in the form of a fan curve.  This fan curve shows the “free air” cfm and static pressure (the two elements of fan performance).  As cfm increases static pressure decreases and as the cfm decrease the static pressure increases (see chart below). 

The equipment manufactures then take a fan and mounts it on the motor shaft; puts that assembly in a cabinet and then restrict the air flow by adding filters (pre-filters & HEPA’s).  This added resistance lowers your motor rpm from 3,500 rpm (in a lab setting) to a range of 2,500 –3,000 rpm (in an actual unit setting).  At this slower rpm you will never achieve the fan manufactures “free air” cfm numbers in the field.   The table below.

12.3" Diameter Fan Performance Table

Performance                        Performance
at 3,500 motor rpm              at 3,000 motor rpm

3,500 cfm @ 0" s.p.              3,100 cfm @ 0" s.p.

3,300 cfm @ 1" s.p.              2,700 cfm @ 1" s.p.

3,150 cfm @ 2" s.p.              2,500 cfm @ 2" s.p.

2,800 cfm @ 3" s.p.              2,200 cfm @ 3" s.p.

2,600 cfm @ 4" s.p.              1,800 cfm @ 4" s.p.

2,250 cfm @ 5" s.p.              1,400 cfm @ 5" s.p.

(this data derived from fan curve chart created by Continental Fan company)

Even though “free air” cfm is not the actual “in the unit/on the job” cfm, is it a good idea to compare vacuum collection systems by comparing the “free air” cfm numbers?  Yes and no.  Yes, if you compare “free air” cfm along with other features like: portability (weight & size), first cost, operating cost (filter replacement), electrical requirements, warranties, etc.  No, if you compare units using just “free air cfm numbers.

If you want a full discussion of this topic I recommend our "How to select an electric portable vacuum collection system guide."  It’s an in depth discussion of what features to compare and why.  Plus, it includes a list/chart of most of the portable vacuum collection units on the market.

A Close Look at the Rotobrush Air Duct Cleaning System

If you think about HVAC system cleaning and what you are trying to accomplish and examine how the Rotobrush system operates and its results you will see some short comings.

The goal of most air duct cleaning contractors is to remove the accumulated dirt, debris and other contaminates found in the HVAC system.  This is called source removal.  The HVAC system includes the supply ductwork and plenum, return ductwork and plenum, grilles/registers, and the furnace or air handler - basically everything in the air steam. 

The primary short coming of the Rotobrush system is its inability to put the ductwork under proper negative pressure.  Putting the ductwork under proper negative pressure is important so the dirt, debris and other contaminates that are dislodged via brushing does not escape through the cracks and seams of the ductwork into the home or buildings occupied space.   In parts of the country with high humidity, proper negative pressure is especially important to prevent any microbial (mold, mildew, etc) contamination in the HVAC system from escaping into the home or building space.

If you look at traditional HVAC system cleaning equipment, they consist of a vacuum collection system, air compressor, and cleaning tools (brushes/air washing/whips, HEPA vacuums, etc).  The vacuum collection system is connected to the ductwork or plenum and puts all or a portion (with zoning) of the ductwork under negative pressure.  Then using the cleaning and agitation tools the dirt, debris and other contaminates are dislodged from the inside of the ductwork.  The light particles are sucked out via suction from the vacuum collector and any heavy particles fall to the bottom of the ductwork.  Then you would push any remaining particles toward the vacuum collector with air washing tools.  The suction or negative pressure from the vacuum collection system also keeps the dirt, debris and other contaminates from escaping through those cracks and seams in the ductwork.

The Rotobrush system does not create enough negative pressure in the ductwork.  The Rotobrush vacuum is located in the center of their brush.  As the brush spins and dislodges the dirt and debris it is throwing that dirt debris and other contaminates forward, backward, right and left.   The suction of the vacuum will pick up the dirt that is close to it but is not strong enough to pick up all the dirt that has been thrown forward, backwards, right and left.   That “thrown” dirt can escape into the home or building space through the cracks and seams of the ductwork and/or it can continue to lie in the bottom of ductwork waiting to be removed.  In round ductwork the loosen dirt and debris falls or is funneled to the bottom of the duct where the vacuum pick up is but there is still dirt and debris in front and behind the brush head/vacuum pick up.  In square and rectangular ductwork the dirt and debris is not funneled anywhere so the Rotobrush will pick up even less of the dirt and debris.   The larger the duct the more dirt and debris is left behind.

Another shortcoming of the Rotobrush system is that it doesn’t include any cleaning tools or the capability to clean a furnace/air handler or coil sections in an HVAC system.  Remember, the goal of most air duct cleaning contractors is to remove the accumulated dirt, debris and other contaminates found in the entire HVAC system.   If you clean just the ductwork and then turn the HVAC system back on, the dirt in the furnace/air handler/coil sections will soon be spread into the supply ductwork contaminating what you have just cleaned.  Rotobrush offers other products for dryer vent cleaning, insulation handling and inspecting but nothing for cleaning the heart of the HVAC system (furnance/airhandler/coil section).

The inability to provide adequate negative pressure and the inability to clean the entire HVAC system are the two primary shortcomings of the Rotobrush air duct cleaning system and others like it.   Before investing your hard earned money into air duct cleaning equipment/tools be sure you have a good understand of its capability and any shortcomings. 

If you have any questions on Rotobrush or any other type of air duct cleaning equipment please call me at 800-597-3955 or 952-808-1619.