I need my airducts cleaned, is the cheapest contractor the right choice?

I'm sure we have all seen the advertisements for a $99 duct cleaning service with unlimited vents.

We are going to discuss the different elements of your heating and cooling system. We will explain how they are connected and why they affect the operation of your system. We will help you understand how they contribute to your dirty ducts. We will also discuss the different types of equipment and techniques used in air duct cleaning to help you better understand the process and effectiveness so you can feel confident when selecting a contractor.

We will start with the simplest subject first. When it comes to particulate matter, the proper filtration is very important. The purpose of duct cleaning is to remove and capture that particulate matter. Without the proper filtration the particulate matter you are trying to remove could be redistributed all through your home. If your contractor is using an ordinary job site canister vac, he most likely isn't going to achieve the results you want.

Now onto the components of your heating and cooling system. No matter what type of system you have, if you have ductwork then your unit has a blower. Most blowers have curved blades that will capture debris. The captured debris will begin to fill the curvature, changing the aerodynamics, causing the blower to move less air, affecting the capacity and efficiency of your system. The blower is what moves the air, so if it is contaminated then it's also contaminating your air.

Next is the evaporator coil. The evaporative coil is a series of loops made of copper or aluminum tubing covered with aluminum fins, much like the radiator of a car. The air in your house passes through the coil. The evaporator coil can capture a lot of debris. This area stays very moist during the cooling season keeping contaminants down. Once the heat is turned on this area will dry out and allow those contaminants to become airborne. A dirty evaporator coil could also restrict airflow reducing the system's capacity and efficiency. It could also make the system freeze during cooling causing possible water damage.

Finally, the reason we are here, the ductwork. A duct system consists of a few different parts. The registers, or vents, that you will see on your ceiling, wall or floor. The registers are normally attached to a branch line. The branch line is either a round duct, flex duct, or smaller sized rectangular duct. The branch line is then attached to the main trunk line. You have both supply and return ducts. The supply "supplies" air to the room and the return "returns" air to the system to be reconditioned. Dirty ducts could slow the velocity of the air reducing the capacity and efficiency of your system. It can also cause harmful particulate matter to be spread through your home. You could experience allergy or flu like symptoms including headaches, sore throat, cough, stuffy and or runny nose, and even respiratory illness.

Now we'll discuss some of the different types of equipment and techniques I've seen advertised.

This technique is common with carpet cleaning companies. The vacuum is connected to the plastic hood and a high-pressure air agitation tool is ran through the branch line from the register boot. The theory is that the air agitation tool stirs up the debris while the vacuum pulls it in.

When using this method the ductwork isn't normally isolated, possibly allowing debris to be pushed to other areas. This also makes the ability to create a negative pressure on the duct system very difficult. This means the correct agitation tools must be used in an almost perfect manner in order to pull the debris back to the vacuum or it wont be removed and may blow through the duct when the system fan is turned back on. Also keep in mind that a residential duct system is usually designed for 800-2000 CFM (cubic feet per minute). Most truck mounted carpet cleaning vacuum's will only pull 600 CFM. Once you subtract the length of the hose the CFM is substantially less. This method is quick but in our opinion very ineffective.

This next one is a portable vacuum with a cable rotary brush attached. It has a long hose with a cable ran through it in which the brush attaches. It also will be fed into the branch line from the register boot but can also be fed into the main trunk line. The intention is for the brush to stir up debris while the vacuum pulls it in. It may be difficult to run through smaller duct and make tight turns. Larger debris may also be harder to remove. When using this method the ductwork isn't normally isolated possibly allowing debris to be pushed to other areas. This also makes pulling a negative pressure very difficult. This method is also quick but in our opinion very ineffective.

The negative air method is the final technique we are going to discuss. This method takes much longer but we use this method because we believe it is the most effective. We start by isolating the main return and supply trunk line from the system. We attach our high-powered (5000 CFM) negative air machine with HEPA filtration to the main trunk line to create a negative pressure. We then seal off every register in the house with plastic sheeting to ensure no debris is going to escape the system and become airborne.

We vacuum each register and register boot with a HEPA vacuum. Next, we run our cable rotary brush down the register boot and through the branch line to remove the tuff debris and to chase any large debris toward the negative air machine.

Then we repeat the process with our high-pressure air agitation tools to sweep the duct. Last, we finish it off with a powerful burst of air. We repeat this with every branch line and main trunk line for both supply and return. Last we clean the register and boot with an EPA approved HVAC disinfectant. The theory is to create a powerful negative pressure to remove any debris while scrubbing, sweeping, and chasing it to and capturing it in the machine.

Before disconnecting the negative air machine, we use a ULV fogger to apply an EPA approved HVAC disinfectant to sanitize your ductwork.

You cannot properly sanitize without creating a negative pressure to pull the solution through the system. Some contractors will try to blow a solution into the return with the system fan running. In our opinion that method is ineffective.

The final step is to clean and sanitize your blower and evaporator coil.

This process takes anywhere from 4-8 hours per system, depending on the size and number of registers.

Unlike many other companies, we believe that if you don't properly clean every aspect of your heating and cooling system, you will not achieve the greatest results. We strive to be the best and we stand behind our work; that is why in our duct cleaning package we include every aspect of your heating and cooling system, without any hidden fees, so you can receive the results you're looking for.

Before you decide on which contractor to hire, ask these 3 questions:

· What equipment and technique will be used?

· What is included in the cost?

· How long will it take to complete?