In the United States, HVAC engineers generally are members of the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE), EPA Universal CFC certified (for installation and service of CFC HVAC devices), or locally engineer certified such as a Special to Chief Boilers License issued by the state or, in some jurisdictions, the city. ASHRAE is an international technical society for all individuals and organizations interested in HVAC. The Society, organized into regions, chapters, and student branches, allows exchange of HVAC knowledge and experiences for the benefit of the field's practitioners and the public. ASHRAE provides many opportunities to participate in the development of new knowledge via, for example, research and its many technical committees. These committees typically meet twice per year at the ASHRAE Annual and Winter Meetings. A popular product show, the AHR Expo, is held in conjunction with each winter meeting. The Society has approximately 50,000 members and has headquarters in Atlanta, Georgia.

Knowing what you should be paying for your HVAC equipment and installation is essential to getting a fair deal. Most HVAC prices aren’t advertised. Contractor strategy is to get a salesperson into your home to sell you on a package of equipment, accessories and installation. This makes comparing systems difficult, and some sales pressure might be applied.
Moisture can enter the duct system through leaks or if the system has been improperly installed or serviced. Research suggests that condensation (which occurs when a surface temperature is lower than the dew point temperature of the surrounding air) on or near cooling coils of air conditioning units is a major factor in moisture contamination of the system. The presence of condensation or high relative humidity is an important indicator of the potential for mold growth on any type of duct. Controlling moisture can often be difficult, but here are some steps you can take:

Two weeks go by and no phone call from HVAC Service regarding install date, or any update at all.  I call them to check in to see if they have put me on the schedule and when I can expect to have the AC installed.    You can tell by the discussion I had with the lady on the phone that they completely forgot about me and have not scheduled anything.  She says she needs to get in contact with the owner because she has no idea on the availability of the crane.  I was told that she would call me back by the end of the day with an update.  Surprise, surprise, no phone call.  

If you’re purchasing from a big-box store, you can expect to pay approximately $120-$1,000 for a window unit. Window units are appealing for their quick setup and relatively low cost, but they can use more energy over time than central air and only cool the room in which they’re installed. The price will vary depending on the type of air conditioner you buy and its cooling capacity. Window units, which require minimal installation, are one of the most affordable options on the market. Portable air conditioners don’t have the cooling power of a window unit, but they do have the perk of being transportable from room to room. Expect to pay between $225 and $800 for a portable air conditioner, on average. The cost of an air conditioning system with coils, condenser and line (not including installation or ductwork) can range from approximately $2,000 to $4,000 or more. If you don’t have (and don’t want to put in) ducts, a ductless mini-split air conditioner is a good option, although pricey up front. Pricing can range from $650 to $4,250 per unit on average; you’ll need one unit for each room in which you want temperature control.
This company deserves more than five stars. They didn't just replace my heater and air conditioner, they built me a new system for my house. Going above and beyond is a understatement. Steve's staff were 2 of the nicest workers I've come across in a long time. Friendly, knowledgeable, and very clean. Truly a top rated company. Thanks Steve.   Great job.
The key to the continued and efficient operation of your heating and cooling system is periodic maintenance. Cleaning the air duct vent system, and servicing you heating and cooling equipment will keep the system operating at its peak performance. Air ducts are cleaned for two reasons. One: to prevent debris from entering furnace and air conditioning components. Two: to prevent debris from cycling through the home. The air duct cleaning contractor needs to employ cleaning methods which successfully removes debris, and ensures that debris does not enter the occupied space. Most contractors can verify the results of the cleaning through video or pictures.
Demand controlled kitchen ventilation (DCKV) is a building controls approach of controlling the volume of kitchen exhaust and supply air in response to the actual cooking loads in a commercial kitchen. Traditional commercial kitchen ventilation systems operate at 100% fan speed independent of the volume of cooking activity and DCKV technology changes that to provide significant fan energy and conditioned air savings. By deploying smart sensing technology, both the exhaust and supply fans can be controlled to capitalize on the affinity laws for motor energy savings, reduce makeup air heating and cooling energy, increasing safety and reducing ambient kitchen noise levels.[29]
At Airco Heating and Air Conditioning, we’re proud of our years of service to the Van Buren area and look forward to helping you with your air conditioning and heating needs. We’re pleased to serve both residential and commercial customers; our team is prepared to help you with the sales, service, and installation of the comfort system that is ideal for your home or business. And be sure to ask Airco Heating and Air Conditioning for a free estimate. Whether it’s a new installation or routine service, our factory-trained technicians provide the expertise your comfort depends on. And at Airco Heating and Air Conditioning, we repair all makes and models.
I own a small mechanical company. My main work is service and system replacements. I have never been a believer in duct cleaning. The company I worked for before had our duct man come out and do my house. I saw no difference. Preventive maintance is what I recomend. Remove fan and clean, seal fan compartment to prevent dust from being pulled in, filters I install media filters, they are 5″ thick and pleated. I have tested them to make sure static presure was not a issue. Heat exchangers and AC coils need to be cleaned. I will tell you this to do a good cleaning I usually spent 1-2 hrs, When I’m finished I would not have a problem eating my diner on the system. Good filters, clean system and properly tuned up are my recomdation to anyone. I’ve included my email feel free to contact me with any questions. winkcfd@yahoo.com
The most recognized standards for HVAC design are based on ASHRAE data. The most general of four volumes of the ASHRAE Handbook is Fundamentals; it includes heating and cooling calculations. Each volume of the ASHRAE Handbook is updated every four years. The design professional must consult ASHRAE data for the standards of design and care as the typical building codes provide little to no information on HVAC design practices; codes such as the UMC and IMC do include much detail on installation requirements, however. Other useful reference materials include items from SMACNA, ACGIH, and technical trade journals.
Preventing against air leakage is great, but the only way to keep dust and debris out of a duct system would be to completely seal off the return-air side of the system, which would render the system useless. Cold-air returns will always pull dust and other particles into the system. A high-MERV rated filter is definitely a good idea, but it does nothing to keep the return side of the system clean. Definitely agree though to use foil tape to seal seams, etc. Duct tape dries out over time and as it does can actually add more particles to the air.
If you’re purchasing from a big-box store, you can expect to pay approximately $120-$1,000 for a window unit. Window units are appealing for their quick setup and relatively low cost, but they can use more energy over time than central air and only cool the room in which they’re installed. The price will vary depending on the type of air conditioner you buy and its cooling capacity. Window units, which require minimal installation, are one of the most affordable options on the market. Portable air conditioners don’t have the cooling power of a window unit, but they do have the perk of being transportable from room to room. Expect to pay between $225 and $800 for a portable air conditioner, on average. The cost of an air conditioning system with coils, condenser and line (not including installation or ductwork) can range from approximately $2,000 to $4,000 or more. If you don’t have (and don’t want to put in) ducts, a ductless mini-split air conditioner is a good option, although pricey up front. Pricing can range from $650 to $4,250 per unit on average; you’ll need one unit for each room in which you want temperature control.
You may be familiar with air ducts that are constructed of sheet metal. However, many modern residential air duct systems are constructed of fiber glass duct board or sheet metal ducts that are lined on the inside with fiber glass duct liner. Since the early 1970's, a significant increase in the use of flexible duct, which generally is internally lined with plastic or some other type of material, has occurred.
Contact/Relay -- Relays are electronically controlled switches that activate the various components of your HVAC system. They manage everything from the power going to the motor to automatic dampers, humidifiers, etc. Most of them are controlled by the thermostat. The most common failure for a relay is being stuck in the "open" position. Separated from its assigned contact point, it fails to complete the connection and send the message to whatever it was supposed to operate. This failure usually occurs from use over time. Each time a relay connects and sends its signal, the electrical arcing from point to point eventually causes wear and tear.
ISO 16813:2006 is one of the ISO building environment standards.[31] It establishes the general principles of building environment design. It takes into account the need to provide a healthy indoor environment for the occupants as well as the need to protect the environment for future generations and promote collaboration among the various parties involved in building environmental design for sustainability. ISO16813 is applicable to new construction and the retrofit of existing buildings.[32]
We moved to a house built in 1965 from a 1915 house with a dirt basement. Against what I anticipated, the 1965 house was much dustier. It was like felt on top of everything. I cleaned and cleaned and it did become less dusty over time. We then found out a cat lady with over 2 dozen cats lived in the house in the past. We then had to get our furnace replaced and I was able to look down some of the duct work, the dirt and debris was 3-5 inches deep. Additionally, the basement ducts were entirely plugged with debris including dirt, seeds, ants, toys, etc. I had already removed what I could from those. We had our ducts cleaned last year, and the dust in the house is greatly reduced. Also have lost the runny nose I got after moving here. There are duct cleaning con artists out there, but ours did a good job.
Humidifiers/Dehumidifiers: Humidifiers add needed moisture to the air in winter and very dry climates. Dehumidifiers remove dampness any time of the year. Central air conditioners dehumidify too, but in very humid climates, you might want to remove humidity without also cooling the air. You have a good range of options for both of these HVAC accessories. Whole-house humidifiers cost $350 to $800 installed, while dehumidifiers are $1,250 to $2,000 or slightly more.

Furnace Circuit Board -- The furnace circuit board controls a variety of functions. It not only handles the regular operation of the furnace, it also monitors the furnace's various safety circuits. Over time, vibrations from the furnace can weaken solder point and cause them to separate. Dirt and debris can cause short-circuits that damage the board. Failure of the circuit board can cause a variety of effects ranging from the fan not turning on to the complete shutdown of the furnace.

1. Ducts need cleaning mostly because they were not installed properly. There should be regulatory inpection and approval of clean and proper duct works on new houses. I was extremely unpset when I looked and found significant amounts of construction dust in parts of the ducts in my new house. There is apparently no way to hold the bullder to be responsible for clean ducts.
1). Busy companies: The company is so busy, it doesn’t need the work. It will add 70% to 100% profit, and if the customer accepts the estimate, it will move that high-margin customer to the front of the line. This often happens in the worst heat of summer when overburdened ACs and heat pumps quit and the dead of winter when furnaces give up. This is a good reason to consider pre-emptively replacing your system once it’s about 15 years old and/or has had major repairs.

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%.
I forgot about a pot of sweet water I had on the stove to boil. When I finally smelled it the kitchen and dining room I=was smoke filled. I mean thick smoke. I opened doors and windows for a few hours to remove the smoke but the smell is still here and terrible. I had to use the AC and that smell started coming out of the vents. Now what do I do? I have COPD emphysema so I have to be very careful about what I inhale. I already have inhaled too much smoke from all of this which has hurt my lungs even more. I can’t afford for them to get worse over this. How can I get the right person to come out and clean the ducts and furnace or is that the only way to remove that burnt smokey smell. The pot never caught on fire but it sure did produce a lot of smoke. I already have replaced the filter on the furnace. It needed it even though it had just been replaced just last week. I need help or really my lungs need help. Who do I call here in Indpls IN.

Knowing what you should be paying for your HVAC equipment and installation is essential to getting a fair deal. Most HVAC prices aren’t advertised. Contractor strategy is to get a salesperson into your home to sell you on a package of equipment, accessories and installation. This makes comparing systems difficult, and some sales pressure might be applied.


BIG THANK YOU for being honest, and advising us that for some reason the fuse/switch was in the reverse position so the AC unit would not properly turn on.   The unit turned back on immediately, and began cooling the house.   And then providing advice that the AC/Heating system needed some TLC, and giving us options to save money by purchasing a maintenance plan that included the filters plus cleaning services since we were already being charged for the service today.
in response to this reply " should your ducts be cleaned", i have to politely correct the person who answered this. you are not using common sense. first, most of the country uses metal duct work, so for you to say what you did, is wrong. second, the duct system in a house is a circulatory system. that means it draws air into the furnace, it gets filtered, and then it is blown out into the house to heat or cool. So, obviously that air is being brought into the house from somewhere right? Yes, its coming from the outside where there are many allergens and dust particles . For you to says that about whether a duct system is sealed or not, makes no difference. The air is coming from somewhere right? It has to originate from somewhere right? Just look on top of your cieling fan. If there is a bunch of dust up there, then there is obviously a bunch in your ducts. And the duct air is being circulated every day, and every hour through your house. Its simple, dust collects everywhere in your house. Imagine if you never dusted your shelves, or tv? There would be a ton of dust after a while. Well, now think about the air in the duct system. Of course theres gonna be a ton of dust in there. For you to say that it is not benififcial to clean the ducts, is plain ignorant. 90% of the air we breathe is in our household. Wouldnt you want that air to be as dust and allergen free? I could go on for hours about the benifits of duct cleaning, but i just wanted to make a quick point that the person whose says it is not benificial to clean them, is not using common sense. Not to mention, giving the people who clean ducts for a living, a bad name. Use your head .
They were quick to come out and diagnose the problem with my furnace, but I thought the estimate of $549 a bit high to replace the circuit board.  So called around and found Leo's Appliance in Concord that sells appliance parts and the circuit board was only $90.49 - that is the retail cost to me, so I imagine the wholesale cost is a lot less.  So BEWARE of this company since they wanted $500!!! to replace the circuit board which is located right in the front of the furnace - extremely easy to access.  I hate it that you cannot trust repair companies.
No matter where you bought your air conditioning system, we can repair it. We have years of experience working with all the best central air conditioner brands such as Kenmore, Carrier. Trane, Goodman, and Rheem. As a result, you can rest assured we’re familiar with your air conditioning system and we have the parts you need to complete a successful air conditioner repair.

They work less jobs, thus increasing profits – think about it…if they got only half of the jobs, then they only pay half of the money required to pay employees, expenses, etc., but still have the same amount of net profit. In fact, if you do the math, they actually make more profit that their competitors do…twice as much, once you factor in their savings form only doing half of the jobs at the same amount of profit (Total Revenue – (half the normal expenses) = twice the profit). In other words, they save money by doing half of the jobs as others, for the same profit, thus increasing their overall profits.
All information provided is provided for information purposes only and does not constitute a legal contract between Wilson's Heating & Air Conditioning and any person or entity unless otherwise specified. Information is subject to change without prior notice. Although every reasonable effort is made to present current and accurate information, LinkNow™ Media makes no guarantees of any kind.
Energy efficiency can be improved even more in central heating systems by introducing zoned heating. This allows a more granular application of heat, similar to non-central heating systems. Zones are controlled by multiple thermostats. In water heating systems the thermostats control zone valves, and in forced air systems they control zone dampers inside the vents which selectively block the flow of air. In this case, the control system is very critical to maintaining a proper temperature.

Did not realize cost had gone up so much for this service. Two years ago I had furnace and ducts cleaned at my old house and it was under $400. Now the cost is $700 for this house. I will keep looking for someone to offer a lower price, check them out, and have it done. Or will find the paperwork to see who did it before. I liked this article and did learn some things. Thanks.
Preventing against air leakage is great, but the only way to keep dust and debris out of a duct system would be to completely seal off the return-air side of the system, which would render the system useless. Cold-air returns will always pull dust and other particles into the system. A high-MERV rated filter is definitely a good idea, but it does nothing to keep the return side of the system clean. Definitely agree though to use foil tape to seal seams, etc. Duct tape dries out over time and as it does can actually add more particles to the air.
Two weeks go by and no phone call from HVAC Service regarding install date, or any update at all.  I call them to check in to see if they have put me on the schedule and when I can expect to have the AC installed.    You can tell by the discussion I had with the lady on the phone that they completely forgot about me and have not scheduled anything.  She says she needs to get in contact with the owner because she has no idea on the availability of the crane.  I was told that she would call me back by the end of the day with an update.  Surprise, surprise, no phone call.  

From furnace installation and heating system installation to air conditioning installation and central air installation, Lowe’s has all your HVAC installation needs covered. Lowe’s will coordinate with independent air conditioner installation professionals to make installing central air a breeze. So stop worrying about how to install an air conditioner and contact Lowe’s to help with your air conditioning install.
If you are using existing ducting, it will have to be inspected. Proper ducting loses around 2% to 5% of your energy. Old, leaking ducts can lose 50% or more. A contractor will need to have the ducts inspected and replace any parts ahead of time. If you are changing the size of your HVAC system because of significant changes to your home, you might need to replace the ductwork regardless.
You can adjust for seasons: During the summer, you can have the air conditioner stay off during the cooler morning hours and start cooling the house as everyone gets up and starts moving around. During the winter, you can have your heater stay off while you are away at work and turn on about a half hour or so before you get home so that you are coming home to a nice, warm house.
Refrigerant Metering Device -- Every HVAC system has one of these, and heat pumps have two. They regulate the amount of refrigerant going through your air-conditioner. If it fails, either too much or too little refrigerant will course along the lines and either not perform well or will overwhelm the compressor and cause it to fail. A total failure of this component will result in a complete loss of operation.
As one of the duct cleaners that do it right it disgusts me to hear the horror stories some of my past customers have had with the companies using scare tactics, bait and switch schemes, and just plain intimidation to make a fast buck. The Ductz franchise as a whole has gone behind other "duct cleaners" in the last year to the tune of almost three-quarters of a million dollars. All of this expense could have been avoided had the customers been able to do some background research before hiring. NADCA is a great organization and should be a minimum requirement for finding a duct cleaner. Other great questions include "How long does the service take?" (2 techs, 4-5 hours for a small house, 7-9+ hours for a two system house), "Do you clean the entire system including all trunk lines and the air handler (blower motor and evaporator coil)?", "How do you validate the job you have done?" (before and after picture reports work great). Beware of duct cleaners that say their process will solve all your air quality concerns. Duct cleaning is one of several steps to take to rid your home of unwanted dust, dirt, mold, and other allergens.
Multiple inventions within this time frame preceded the beginnings of first comfort air conditioning system, which was designed in 1902 by Alfred Wolff (Cooper, 2003) for the New York Stock Exchange, while Willis Carrier equipped the Sacketts-Wilhems Printing Company with the process AC unit the same year. Coyne College was the first school to offer HVAC training in 1899.[12]
I'd have to disagree with all of your statements. Not only are they derived from no experience in the field, you are missing keys facts. Ducts even if air tight will get dirty. If they are not getting dirty, it means they are not working. Your returns side of the duct work is always under negative pressure when the system is operational.Therefore it is always drawing air in. Seeing how dust is made up mostly from dead skin humans shed daily. Around 1.6 Pounds of skin a year per human. Living in your home anything that is air born will be drawn back towards the cold air returns. That is what they are designed for, to draw stale air back to the system to be filtered and sent back through the house.Homes with carpet will actually have cleaner duct work than home with all tile or hardwood. This is because carpets hold onto dust particles and you vacuum them up. Whereas on hardwood or tile, dust can run freely back to the returns. Even if a duct system was sealed 100%, which is next to impossible to achieve 100% would still need to be cleaned. The cleaning may only have to be every 7-10 years for example. Most homes require every 5-7 years. And that's if it was done properly the first time. If you constantly hire people that have no or minimal knowledge of duct cleaning, You home would require cleaning more often. Every 2 years. That's a trade secret, The longer they recommend before the next cleaning, the odds are they did it right. That's not to say there aren't people that lie, because there are. Just have your duct cleaner take pictures before and after cleaning. Not just an outside view. Get in there, picture entire joist liners, Whole main runs and even long round pipes. Also it helps to have a company that guarantees their work. If it's not done right, they will come back and do it until it is. Most companies that do this make sure it is right the first time. Your not getting paid to do the job twice.
I did the $49.00 Groupon they just left. Basiclly all they did was stick a shop vac type hose into the vent supply and one return. I also had the dryer done. the person in charge pointed to the main return inside my humidifier and said it needed cleaning. I explained that I was in facility maintaince and would deal with it myself. After that they finished the vac and didn’t try any other sales pitch. I should have read the reviews before I bought this wast of money and time.

I just had my Air ducts “cleaned”. The person who came to my house works for an air duct cleaning company who uses a professional vacuum. He said the company would charge me about $900 but he can do it aside on his own and charge me half of that. However, when he came over the house, he brought the rotary brush along with his domestic vacuum cleaner that it’s hose was about 5 feet long, I ask him that the wasnt strong enough to pull dust out, and he said, it’s similar to what companies use. I was in doubt and he didnt cover the vents so im thinking all dust must have come out from every air vents. Could this vacuum have taking the debris out of the air ducts? Or how can I myself find out if the inside of the air ducts have been cleaned and no debris is sitting there? I have dust all over my house.


Heating, ventilation, and air conditioning (HVAC[1]) is the technology of indoor and vehicular environmental comfort. Its goal is to provide thermal comfort and acceptable indoor air quality. HVAC system design is a subdiscipline of mechanical engineering, based on the principles of thermodynamics, fluid mechanics and heat transfer. "Refrigeration" is sometimes added to the field's abbreviation, as HVAC&R or HVACR or "ventilation" is dropped, as in HACR (as in the designation of HACR-rated circuit breakers).
Natural ventilation is the ventilation of a building with outside air without using fans or other mechanical systems. It can be via operable windows, louvers, or trickle vents when spaces are small and the architecture permits. In more complex schemes, warm air is allowed to rise and flow out high building openings to the outside (stack effect), causing cool outside air to be drawn into low building openings. Natural ventilation schemes can use very little energy, but care must be taken to ensure comfort. In warm or humid climates, maintaining thermal comfort solely via natural ventilation might not be possible. Air conditioning systems are used, either as backups or supplements. Air-side economizers also use outside air to condition spaces, but do so using fans, ducts, dampers, and control systems to introduce and distribute cool outdoor air when appropriate.
An AC contactor is a $25 mechanical relay that uses low-voltage power from the thermostat to switch 220-volt high-amperage current to the compressor and condenser fan. AC contactors can wear out and are at the top of the list of common air conditioning service failures. Even if your AC contactor is working, it pays to replace it every five years or so. Unscrew the old AC contactor before removing the wires. Then move the wires to the new unit (Photo 6).
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