One of the difficulties encountered by many air duct cleaning service companies is that their attention is not really on air duct cleaning. For example, many heating and cooling companies offer duct cleaning as a supplemental service, but of course their primary business is installing and servicing heating and cooling equipment. For these companies, air duct cleaning is not always given the attention it deserves and is often done by less experienced employees whose interest is not in duct cleaning but in repairs and installs. And it is almost always done with inferior air duct cleaning equipment. Still other firms (like carpet cleaners) offer a large variety of services and claim to “do everything.” Because of their lack of focus they may not actually be very good at many, if any, of the services they offer. They cannot simply buy an attachment for their carpet cleaning machine and magically become a great duct cleaner.

Bigger is not necessarily better when it comes to HVAC systems, and smaller isn't always more efficient. If you have too small of a system, your system will be running constantly as it tries to keep up with the temperature. If you have too large of a system, it won't run long enough to keep up with the humidity. In order to handle both temperature and humidity efficiently, an HVAC system should run for around 30 minutes at a time. If your system is staying on too long or shutting off after only around 10 minutes, you are not getting efficient performance.
I call to follow up at the end of the next day and she said that she has not been able to get in touch with the owner.  By this time, I am starting to get frustrated because I am starting to get the run around.  I question her if I am even on the schedule or if they attempted to schedule a crane.  She says they are extremely busy and that she does not know.  So I say, basically I have waited over 2 weeks and you have not put me on the schedule and I am at the end of the install line.  No answer.  I tell her to talk to her boss and find out what is happening, and I will think about what direction I want to move in at this point.  
An alternative to packaged systems is the use of separate indoor and outdoor coils in split systems. Split systems are preferred and widely used worldwide except in North America. In North America, split systems are most often seen in residential applications, but they are gaining popularity in small commercial buildings. The split systems are a great choice for small buildings where ductwork is not feasible or where the space conditioning efficiency is of prime concern [20]. The benefits of ductless air conditioning systems include easy installation, no ductwork, greater zonal control, flexibility of control and quiet operation [21]. In space conditioning, the duct losses can account for 30% of energy consumption [22]. The use of minisplit can result in energy savings in space conditioning as there are no losses associated with ducting.
I spent a lot of time reading all these posts and frankly I can’t believe the way some people think. 1. If there is dust and dirt of any kind in my HVAC system I want it out, the mentality that it can stay there and it’s fine is fulish as the system turns on and off microscopic particulates will move in and out of your living space and you will definitely breath them in. The air quality of your home or office will only be as clean as the system that produces it. We don’t not clean things simply because we can’t see them, it’s what we can’t see that can do the most harm. Dust will build up in a system fairly quickly and will get damp at times allowing mold to grow and mold releases spores without any movement as part of its defense meconisam so don’t tell me that when your system turns on it won’t blow the spores out into the living spaces of your home. A build up of dust will cause failures to your system over time, equipment that works harder to do its job will run hotter with more strain and this will lead to brake downs and until then the system will run less efficient then it should. The system was engineered to move a certain volume of air through a specific duct size, when that duct size starts to become narowed down with dust build up your system has to work harder to move that air this is why you will end up with a loss of efficiency and eventually breakdowns or failures. I have seen systems develop a significant amount of dust build up in as little as two years, just look at how fast the filter gets clogged up and it isn’t all that hard to believe. As for all the scams that are out there they hurt the industry because people can’t decipher between them and the legitimate companies, BBB is helpful. Recommendations from HVAC contractors will be a good resource and a good company will provide a written estimate with a complete brake down of what they are going to do and why, most of which is comen sence once they explain it to you, then if you spend about 5 minutes watching them once they are set up you can see they are doing what they said they would do and let’s get real would you do a job that should take approx 3 hours per system for $29/$39/59 or something close to that, if you think you are going to get a good job from a comp that has to make money at that price you shouldn’t be mad at anyone but your self for trying to get quality work at a scam price. If it’s done right it will be very beneficial and depending on the size of your system and where you are in the world it’s going to cost you approx $300 to $600 per system large and or older systems may cost even more. Remember a quality job isn’t wasting money but a lousy job is, even if it’s only $29. I’d rather spend $600 on a quality job then $29 on a lousy job!! Good luck..
Air conditioning and refrigeration are provided through the removal of heat. Heat can be removed through radiation, convection, or conduction. Refrigeration conduction media such as water, air, ice, and chemicals are referred to as refrigerants. A refrigerant is employed either in a heat pump system in which a compressor is used to drive thermodynamic refrigeration cycle, or in a free cooling system which uses pumps to circulate a cool refrigerant (typically water or a glycol mix).
After one company just took a cursory glance at our A/C and found nothing wrong, I called HVAC. I called them mostly based on Michael W's post on 8/10/14 where he told us the owner, Alberto, took his feedback and took it SERIOUSLY. That speaks VOLUMES to anyone who has been around long enough to know the characteristics of the serious players are and those who are the wannabes.

An air conditioning system, or a standalone air conditioner, provides cooling and humidity control for all or part of a building. Air conditioned buildings often have sealed windows, because open windows would work against the system intended to maintain constant indoor air conditions. Outside, fresh air is generally drawn into the system by a vent into the indoor heat exchanger section, creating positive air pressure. The percentage of return air made up of fresh air can usually be manipulated by adjusting the opening of this vent. Typical fresh air intake is about 10%.
We hope you found this article on a fair HVAC installation cost helpful. In the end, you’ll be alright so don’t worry too much. Do your research on reputable air conditioning contractors in your area, and spend time making sure that you have a company that you can trust – it will cost you less in the long-run, trust me. Take your time, follow the tips above, and you will end up with an HVAC installation cost that is more than reasonable, keeping your family comfortable for years to come. For more on topics like this, see: ASM’s Air Conditioning Blog.
Pay particular attention to cooling coils, which are designed to remove water from the air and can be a major source of moisture contamination of the system that can lead to mold growth. Make sure the condensate pan drains properly. The presence of substantial standing water and/or debris indicates a problem requiring immediate attention. Check any insulation near cooling coils for wet spots.
Prices for central-air HVAC systems will vary. The national average to hire an HVAC specialist is $2,920-$3,670 but can run as high as $5,000 or even $12,000 depending on the capacity you need and other factors. Installing central air conditioning requires an entire system that works together to draw hot air out of your home. The system includes an outdoor unit, which houses the condenser and compressor, and the evaporator coils. If you don’t have an existing duct system, ductwork will need to be installed, which will affect labor and material costs. Leaking or damaged ducts will also need to be replaced.

Here in Atlanta we get 6 to 10 $49 coupons in the mail weekly…I have always consider them a complete scam….just had my master bathroom& bedroom and guest bath completely remodeled down to the studs…Had my 3 returns nearest the area sealed to prevent sheet rock dust to spread…it worked and I personally cleaned all 7 returns when a 5 HP , new Rigid shop Vac($99 from HD)…took one hour and I found little evidence that “I need my ducts cleaned” Had quotes from $400 to $600…I use the best air filters for my air handler and change it every 2 to 3 months…..any dust is trapped in it and I believe the Air Duct folks are all cons….
Clean the condenser fan blades before the start of the cooling season. Brush any dust or debris off gently and then uncover the condenser coils, gently cleaning the dirty side. Then wrap the motor and other electrical components in plastic bags and gently spray from the inside with a hose. Now check the base pan under the unit and clear it out of any debris that has gathered.
Most people are now aware that indoor air pollution is an issue of growing concern and increased visibility. Many companies are marketing products and services intended to improve the quality of your indoor air. You have probably seen an advertisement, received a coupon in the mail, or been approached directly by a company offering to clean your air ducts as a means of improving your home's indoor air quality. These services typically — but not always — range in cost from $450 to $1,000 per heating and cooling system, depending on: