I am a service technician [since '92].....and as to double filtering.....I have never recommended it. Granted.....it would be noticeably helpful if the fiberglass filters are the main ones used [which I also never recommend.....as long as system can deliver appropriate air flow with a pleated cotton filter...and any decent service tech can check the air flow for proper cfm]. Any particles small enough to pass through a pleated cotton filter are going to pass through a second filter as well....unless the second filters are so tight that the system is starving for air flow. Has anybody ever accidentally put two filters in their automatic drip coffee maker? What if cars used two fuel filters or air filters? I have told some homeowners to try using second filters at each register [the black thin filter material cut-to-fit....same type used in many window air conditioners].....but I only suggest this when I know they will still get at least 400 cfm per ton of air flow [350 absolute minimum]......as some homeowners know others who say it has helped and it gives them a peace of mind knowing they are doing something to help contribute to a solution, so it HAS to help [even though I think it falls in the "one-born-every-minute" category.....similar to duct cleaning].
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.

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 am in need of HVAC ADVICE!! I need a new furnace badly, mine is cracked. I have bought both a 95 % AFUE furnace and a 5 Ton evap coil, I figured it should all be replaced at once for both cost and efficency. My question is with all the negaitive things I have heard about companies ripping you off, what type of price should I pay someone for putting in those two items and bringing everything in my attic up to code? I have been quoted $550 - $ 3300. Wide margin here!! Then of course comes the licencing part!! I know in my heart that I should use a licenced contractor but I have had such bad luck and prices from them that honestly one that was licened in Ga. and just not here in TN and is a tech. which charges 1100 - 2200 less sounds good as so long as I pay some type of Profenial HVAC person say $100 to inspect the work after its done and before I pay them.
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.
The EPA is so far behind on useful knowledge because of the lack of funding so don't be mislead. The Hvac old timers were left at the dock so to speak and missed out on the IAQ movement. The ones that are savvy and up to date on the information do Air Duct Cleaning, even tho that will lead to a few less service calls its the right thing to do for their customer. Please take a look into a return duct that has never been cleaned, I dare anyone to say it does not need to be cleaned.
I am NADCA Certified Air Systems Cleaning Specialist. Over the years I have learned on simple answer to this questions: there air duct cleaners and there are pretenders. There will be no benefit at all if you use on the very cheap pretender because they will not really clean anything. On the other hand if you call a qualified air duct cleaner with a NADCA Certification you will, like 99% of my customers, report improvement with your respiratory problems, you will see less dust and the job will pay for itself with energy savings and repair prevention.

I know it has to have a new concentric venting system installed, I believe it needs new plenums ( mine are rusty but both of these require extra work , so someHVAC persons are saying I do not need either!! RED FLAG THERE. Also, it will need a new drain using PVCP ?? Piping run maybe two, depending on where my evep coil drain is conected (here in TN they use to run them in with the septic lines, now they cannot be run through that way), Lastly I am not where or what these things do beides hold water but I was told It needs a filter rack and new filter base safety pan. THATSSS it that is all I know about this stuff aside from the fact that nothing up there is to code thus far LOL. !!


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.
It's always changing: Some newer thermostats take advantage of wireless technology. You can adjust your thermostat remotely so that if you leave and forget to adjust it, or if you are going to be home later than you thought, you can adjust it via your smartphone. Some can even give you reports on how efficient your system is performing based on usage. These are very efficient models, but they are also very expensive with some costing over $250.00.
Air duct cleaning service providers may tell you that they need to apply a chemical biocide to the inside of your ducts to kill bacteria (germs) and fungi (mold), and prevent future biological growth. Some duct cleaning service providers may propose to introduce ozone to kill biological contaminants. Ozone is a highly reactive gas that is regulated in the outside air as a lung irritant. However, there remains considerable controversy over the necessity and wisdom of introducing chemical biocides or ozone into the duct work.
Cost Factors: The size of the unit, its efficiency and it’s single-stage, two-stage or variable-capacity are the top cost factors. Features like communicating technology and improved dehumidification performance also affect the price. Learn more about communicating technology here including the pros and cons, before being agreeing to a communicating system.
What you might not know is that the brand you choose is one of the most important factors in determining a fair HVAC installation cost. So, before delving in-depth, let’s take a quick look at the average prices of a new air conditioner and matching coil by brand…keep in mind, these are the average prices (by brand) that contractors pay for your AC equipment, and it is meant to give you a rough guideline until you are closer to buying:
SEER is useful for comparing one model to another much in the same way that a car's calculate MPG is useful. It's not an accurate prediction of exactly how efficient the system is, but it can tell you which one is more efficient. Also, since SEER is based on a "cooling season", what region you live in will determine how long or short your cooling season is.
Sounds like your first hvac company was ripping you off. Ask your new company to go to your coil and see if there is a leak. If there isn't the last company was just lining their pockets. If you have had ducts unhooked for a long time I would recommend duct cleaning, trust me I'm not a fan of duct cleaning myself. I have done hvac for 20 yrs. in GA. When I just bought a home built in 1996, we had all the ducts replaced immediately.
So HVAC sent Tony Diaz to my house. I was at work so he was subjected to the most excruciatingly exacting woman on the planet (my wife). Tony impressed her with his friendliness, professionalism and the obvious jouneyman-level knowledge of his craft. He found literally --burnt-out-- parts in our system and replaced them. It cost us a bit but I know enough about the parts to see there was no gouging on the parts and a fair rate for the labor. It wasn't cheap but it was fair and worth every dime.
An air conditioner's compressor contains a refrigerant. As it works, it sends this refrigerant through the system. As warm air blows across the coil that carries this refrigerant, the heat transfers to the refrigerant (cool always absorbs warm). A fan moves the cooled air through the ducting and out of vents that lead into the rooms of your house. The refrigerant returns to the compressor where the absorbed heat is moved outside. The refrigerant is then sent through the coil once again to continue the cycle.
I was able to get a next day appointment with them last week after multiple other providers did not have availability. The tech was on time and did a good job to diagnose and eventually replace the circuit board and get it up running again. The service itself would be 5 stars, although it did take a week to complete the job due to ordering the part.

You might also want to check your home for thermal insulation if you live in extreme heat or freezing temperatures. Insulation keeps the heat and cool air in your home, which can lead to a lower electric bill. If the heated or cool air leaks out, your system turns on more often. There are various types of insulation that you can install in your home and a home energy auditor can point out the best places for it in your house.
Concrete Blocks -- Concrete blocks are used in foundations and are often found in full basements. Insulating the spaces in the blocks is not the way to insulate them as the heat energy will travel along the concrete itself. The best way to insulate with concrete blocks is to use insulated concrete blocks, which have polystyrene incorporated into them.

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.


Chemical biocides are regulated by EPA under Federal pesticide law. A product must be registered by EPA for a specific use before it can be legally used for that purpose. The specific use(s) must appear on the pesticide (e.g., biocide) label, along with other important information. It is a violation of federal law to use a pesticide product in any manner inconsistent with the label directions.
Engineers have pointed out some areas where efficiency of the existing hardware could be improved. For example, the fan blades used to move the air are usually stamped from sheet metal, an economical method of manufacture, but as a result they are not aerodynamically efficient. A well-designed blade could reduce electrical power required to move the air by a third.[28]
Dehumidification (air drying) in an air conditioning system is provided by the evaporator. Since the evaporator operates at a temperature below the dew point, moisture in the air condenses on the evaporator coil tubes. This moisture is collected at the bottom of the evaporator in a pan and removed by piping to a central drain or onto the ground outside.
The AC contactor (relay) and start/run capacitor(s) (see illustration below) fail most often and are inexpensive. So it's a safe bet to buy and install those parts right away, especially if your air conditioning service unit is older than five years. The condenser fan motor can also fail, but it runs about $150 — hold off buying that unless you're sure that's the culprit.
×