Categorys
Pages
Linkpartner


    Page 13«..10..12131415..2030..»



    Why Your Central AC Isn’t Moving Enough Air – Popular Mechanics - July 4, 2017 by Mr HomeBuilder

    My central air- conditioning system doesn't seem to be moving much air. What's the problem?Laura I., Boise, Idaho

    Of the things that can contribute to lack of air movement, some are simple enough for you to check. For others, you'll need a contractor.

    If the system seems to have slowly and gradually lost air movement, that could be a dirty evaporator coil or air filter. It takes a lot of neglect and a lot of airborne dirt to cause an air-blocking buildup, but it can happen. For example, if your home went through a long phase of remodeling and the contractors didn't do much to keep flying dust under control, that could be the cause. Have a look at the filter, and, if you know where to find it, check the evaporator coil, too. Another source of slow loss of air movement is a fan that's not operating properly. Normally fans and blowers either work or they don't, but one that runs intermittently or is turning slowly (and perhaps even overheating) could cause the problem.

    Advertisement - Continue Reading Below

    If the problem occurs suddenly, it could be the ducts. A flex duct (essentially, a large insulated hose) that has detached or been pinched could suddenly prevent air flow. A quick look in the attic is all it takes to spot this. Similarly, if a duct-cleaning company didn't send its A-team, they might have damaged the system or knocked loose a piece of rigid insulation inside a steel duct. This would have the same result.

    If the problem appeared soon after having a new system installed, you need to get the contractor back. The problem might be obvious, like a closed damper, or it might take some sophisticated pressure testing to reveal whether there is improper duct sizing or an air filter that's just too restrictive.

    Go here to read the rest:
    Why Your Central AC Isn't Moving Enough Air - Popular Mechanics

    Why Air Duct Cleaning is Important for Family Health – Press … – Press Release Rocket (press release) - July 4, 2017 by Mr HomeBuilder

    Dallas, TX It is that time of year again summer. With one of the hottest summers on record, households are becoming increasingly reliant on their central air conditioning to provide reprieve from the unforgiving heat. Dallas and Fort Worth are consistently hitting mid-to-high 90s in the forecast for the conceivable future.

    The company Pure Airways has been making news online in the Dallas/Fort Worth area about their air duct cleaning and duct insulation repair services. According to Direct Energy, dirty air ducts are a leading cause of allergies caused by pet hair, dander, and dust mites. Direct Energy recommends that homeowners regularly have HVAC duct cleaning performed by a professional cleaning service.

    With exacting heat and humidity, HVAC systems will be utilized now more than ever and their chances of being taxed by clogged air ducts is ever increasing. Summer is a typical time for HVAC systems to be burdened by heat and frequent use, ultimately failingand needing tobe repaired.

    Many different things can cause the house to be filled with dust and other particles. Dead skin cells and cooking that is accompanied with smoke will cause some of the largest buildup of dust in the vents and ducts. Dust particles from smoke are often oil based and can easily pass through the air filters on HVAC systems.

    Fuel operated furnaces will also lead to health issues overtime. Carbo Monoxide can be absorbed into the air duct material overtime and those chemicals can then be dispersed into the living space to cause breathing problems, lethargy, and headaches.

    The Dallas/Fort Worth area is one of the most humid in the country. This humidity will cause a buildup of mold and mildew in the HVAC ducts. Based on information from the Environmental Protection Agency, air vent cleaning should be done when dust and mold is present in the home. Professional cleaning services like Pure Airways are usually called in to perform thorough cleanings of the HVAC system when mold is present.

    With summer fully underway and families spending more time at home, household health is increasingly important. Homeowners dealing with allergies will be looking to HVAC cleaning services like Pure Airways to trade a costly utility bill for a clean bill of health.

    Media Contact Company Name: Pure Airways Contact Person: Media Relations Email: pureairways@gmail.com Phone: (888) 717-3224 Address:13333 N.Central Expy City: Dallas State: TX. 75243 Country: United States Website: http://www.pureairways.com/

    Continue reading here:
    Why Air Duct Cleaning is Important for Family Health - Press ... - Press Release Rocket (press release)

    AirDuct – AirDuct Cleaning Services in the Washington DC … - November 29, 2016 by Mr HomeBuilder

    We offer a number of services, but only one main goal-make every home safe, clean and beautiful!

    Our combined expertise in water damage restoration and home remodeling allows us to take a holistic approach to our work. We have the technical knowledge and the renovation experience to safely and effectively eliminate water and mold and restore your home to a new condition.

    We also offer superior air duct and carpet cleaning services and professional carpentry work. Throughout all of our work in D.C., Maryland and Virginia we are dedicated to delivering quality work with our technical expertise, reliable equipment and personalized customer care.

    The Services We Offer

    Water Damage Restoration: Using three-step procedure our expert technicians can effectively minimize the damage caused to your home.. Click here to read more

    Home Renovation: Our skilled craftsmen have experience in millwork, built-in cabinetry and a variety of home improvement projectsClick here to read more

    Air Duct Cleaning: We eliminate dust and allergens that quickly accumulate in your HVAC system and threaten the quality of your air.. click here to read more

    Carpet Cleaning: Using a deep cleaning method we effectively rid stains, refresh your home and guarantee 100% satisfaction click here to read more

    Mold Remediation: We identify, eliminate and remediate mold so that your not at risk for allergens, repository problems or other health concerns, click here to learn more

    See the original post:
    AirDuct - AirDuct Cleaning Services in the Washington DC ...

    2016 Air Duct Cleaning Costs | Average Price to Clean Vents - November 26, 2016 by Mr HomeBuilder

    The average national cost to clean ducts & vents is $341, with most homeowners spending between $242 and $440. This data is based on actual project costs as reported by HomeAdvisor members.

    Did you know that cleaning your ducts and vents can help airflow and increase energy efficiency? According to the Environmental Protection Agency (EPA), duct and vent cleaning can increase energy efficiency and indoor air quality. While the cost to clean ducts and vents might sound high, the benefits to homeownersespecially those sensitive to allergensis worth considering.

    When a professional cleaner comes into your home to clean air ducts and vents, that means they will clean all the different elements in the HVAC system, including the supply and return air ducts, grilles, diffusers, exchangers, heating & cooling coils, drip pans, fans and the air handling unit.

    When these aren't properly maintained, they can build up dust, pollen and even mold. This means when the air conditioner or heater turns on, the spores are released into the air for you to ingest. While some are less harmful, people who have allergies or sensitivity to certain spores will react negatively. Plus, mold is just dangerous for anyone to ingest and should be avoided by regularly duct and vent cleaning.

    In most modern homes with up-to-date heating and air conditioning systems, filters are changed regularly through the year, so you may not even need to have your ducts and vents cleaned. However, keep your eyes open for the accumulation of dust, dirt and mold. If you see it despite regularly changing your filters it could be an indication you need your ducts cleaned.

    One of the best ways to know if your ducts or vents need to be cleaned is to just check them. Your eyes will be able to check for indications of mold, dust or pollen buildup in the ducts and vents. You might also be able to smell the presence of mold, which would be a clear indicator there is some in the ducts or vents. Ductwork will have some buildup of dust, since the return registrars pull air back in. However this doesn't mean your ducts have too much debris, and you can easily clean them with a duster or vacuum.

    If you do have children or spouses who suffer from allergies or reactions to the air turning on, it might be an indication there is something in the ducts and vents making them react. They should speak with their doctors and thenget a heating and cooling professional out if it is recommended that airborne pathogens are the cause of their reaction.

    Here are some clear signs that you might need ducts or vents cleaned:

    A do-it-yourself approach will only really scratch the surface, as it is hard to reach some of the ventilation running underneath the floor or into the wall. Although it may help in clearing some of the dust and debris, you really need a professional cleaner to guarantee your system is truly cleaned out. A proper duct and ventilation cleaning procedure uses a powerful vacuum system with multi-brush attachments designed to loosen debris and feed it into the suction. Particles are then blown outside of the house or passed through a HEPA filter inside.

    If you want to get some of the dust and debris out of your ventilation system, you can mix household cleaners like bleach with water, dip a cloth in the mix and then the clean out the system. This will remove a layer of the spores, which could increase the quality of air a bit and help with the flow of air throughout the house until a professional cleaner can come out.

    Professional air duct and vent cleaning involves getting the dust and debris outside, so they use outdoor ventilation equipment. It is so important that homeowners make sure the professional is using good equipment then, as they could otherwise spread the spores into the home and further agitate sensitive family members. In the case of mold, a cleaner will only be able to tell you it is there, followed by needing an additional mold professional to come out and test or remove the mold. Air duct cleaning industry does not require state licensing in many states, so make sure to check for a company with references.

    Removing dust and debris from ventilation might require the professional getting down on the floor if you have floor vents, so be sure to speak with them about your furniture and other valuables near the vents to avoid any damages or problems.

    Your duct system can be treated with a sealant. These sealants prevent dirt and dust from getting sent back into the air. Sanitizer chemicals can also be added to prevent the growth of mold and other allergens. This is a possible solution for saving on fewer duct cleanings in the future.

    Read more:
    2016 Air Duct Cleaning Costs | Average Price to Clean Vents

    Westchester Air Duct Cleaning Inc. Westchester’s air duct … - November 25, 2016 by Mr HomeBuilder

    Serving: All of Westchester, New York, New Jersey, Connecticut, Armonk, Briarcliff Manor, Bedford Hills, Cross River, Katonah, Pelham Manor, Croton-On-Hudson, Chappaqua, Hastings, Pleasantville, Mt Kisco, Cortlandt Manor, Montrose, Buchanan, Verplank, Putnam County, Somers, North Salem, South Salem, West Harrison, Irvinton, Tarrytown, Yonkers, Sleepy Hollow, Dobbsferry, Hawthorne, Valhalla, Bronx, Manhattan, Ardsley, Scarsdale, Bronxville, Millwood, Armonk, Croton Falls, Mamaroneck, Rye Brook, Larchmont, Ossining, Pound Ridge, Port Chester, Shrub Oak, Yorktown, Eastchester, Hartsdale, Tuckahoe, Elmsford, Goldens Bridge, Waccabuc, Thornwood, Mohegan Lake, Buffalo NY, Erie County, Monroe County, Niagara County, Chautauqua County, Ontario County, Wayne County, Cattaraugus County, Livingston County, Genesee County, Allegany County, Orleans County, Wyoming County, Barker Village, Cambria Town, Gasport Cdp, Hartland Town, Lewiston Village, Lockport Town City, Middleport Village, Newfane Town Cdp, North Tonowanda City, Olcott Cdp, Pendleton Town, Porter Town, Ransomville, Rapids Cdp, Royalton Town, Sanborn Hamlet, Somerset Town, Wheatfield Town, Wilson Village Town, South Lockport, Youngstown Village, Akron Village, Alden Town Village, Amherst Town, Angola On The Lake Hamlet, Angola Village, Aurora Town, Billington Heights Hamlet, Blasdell Village, Boston Town, Brant Town, Buffalo City, Cheektowaga Town, Clarence Center Hamlet, Clarence Town, Colden Town, Collins Town, Concord Town, Depew Village, Derby Hamlet, East Amherst Hamlet, East Aurora Village, Eden Town, Elma Center, Elma Town, Evans Town, Farnham Village, Gowanda Village, Grand Island Town, Hamburg Town, Hamburg Village, Harris Hill Hamlet, Holland Town, Kenmore Village, Lackawanna City, Lake Erie Beach Hamlet, Lake View Hamlet, Lancaster Town, Lancaster Village, Marilla Town, Newstead Town, North Boston, North Collins Town, North Collins Village, Orchard Park Town, Orchard Park Village, Sardinia Town, Sloan Village, Snyder Hamlet, Springville Village, Tonawanda Town, Tonawanda City, Town Line Hamlet, Wales Town, West Seneca Town, Williamsville Village, Rochester County, Ulster County, Accord, Bearsville, Big Indian, Bloomington, Boiceville, Chichester, Clintondale, Connelly, Cottekill, Cragsmoor, Denning, Ellenville, Esopus, Gardiner, Glasco, Glenford, Greenfield Park, High Falls, Highland, Highmount, Hurley, Kerhonkson, Kingston, Lake Hill, Lake Katrine, Lloyd, Marbletown, Marlboro, Milton, Modena, Mount Marion, Mount Tremper, Napanoch, New Paltz, Olive Bridge, Phoenicia, Pine Hill, Plattekill, Port Ewen, Rifton, Rochester, Rosendale, Ruby, Saugerties, Shandaken, Shokan, Spring Glen, Stone Ridge, Tillson, Ulster Park, Walker Valley, Wallkill, Warwarsing, West Camp, West Hurly, West Park, West Shokan, Willow, Woodstock.

    Read more from the original source:
    Westchester Air Duct Cleaning Inc. Westchester's air duct ...

    Air Duct Cleaning Houston | Abacus - November 14, 2016 by Mr HomeBuilder

    Air Duct Cleaning For Houston Homeowners

    Knowledge about air duct cleaning is in its early stages, so a blanket recommendation cannot be offered as to whether you should have your air ducts in your home cleaned. Duct cleaning has never been shown to actually prevent health problems. This is because much of the dirt in air ducts adheres to duct surfaces and does not necessarily enter the living space. It is important to keep in mind that dirty air ducts are only one of many possible sources of particles that are present in homes.

    he purpose of this video is to loop at tradeshows or to be sent out to people with questions about duct cleaning.

    According to the national Air Duct Cleaners Association (NADCA), the average six-room house collects 40 pounds of dirt, dust and allergens in its air ducts each year. Thats a big problem, considering that 40,000 dust mites can thrive in only one ounce of dust. Those little dust bunnies contain a host of unhealthy bacteria, fungi and mold. The EPA estimates indoor air can be two to five times more polluted than outdoor air. Even worse, the contaminated air circulates throughout your house every time the heating or cooling system kicks on.

    Your wallet takes a hit as well. The build-up of dirt and debris prevents the air from flowing freely throughout the ventilation system. That means it works harder and costs more to operate. Over time, the problem only gets worse. Clear the air in your home with air duct cleaning and air vent cleaning services from the NADCA certified professionals at Stanley Steemer.

    Its also important to realize that many companies limit ventilation system cleaning to the air ducts. Not Stanley Steemer. We clean your entire ventilation system, including the HVAC unit, blower, evaporator coil and accessible components, as well as the individual air ducts, from the vent covers to the main trunk line. We also remove the vent covers, clean them, and then put them back in place. From duct cleaning to vent cleaning, we clean every part of your ventilation system.

    In addition to air duct cleaning, our certified technicians also clean dryer vents. having your dryer vents professionally cleaned regularly not only saves you money in energy efficiency, it can help prevent a dryer fire in your home.

    Watch for the following signs that an air duct cleaning is overdue:

    Dirty supply and return vent covers.

    Dark filtration lines on the walls, ceiling or carpet that surround the vents.

    Excessive dust in the home.

    Variance in temperature or air flows throughout the house.

    An increase in the energy needed to operate the HVAC system at desired settings. This may indicate that dirt and debris are blocking coils and/or ductwork, restricting flow and spiking utility bills.

    New furnace or ductwork.

    A recent remodel/construction project.

    Water damage or flooding that occurred in the ductwork, which could cause sediment build-up in the system.

    Indoor air quality is one concern that homeowners have when they decide to investigate air duct cleaning. Your heating and cooling system is the lungs of your home. The system taken air in and breathes air out.While dirty ducts dont necessarily mean unhealthy air in your home, school or workplace, they may be contributing to larger health issues or harboring contaminants that could cause serious problems for people with respiratory health conditions, autoimmune disorders or some environmental allergies. Call (713) 812-7070us for your home service and repair needs.

    For more related articles and infohttps://www.abacusplumbing.net/category/air-conditioning/

    Read the original:
    Air Duct Cleaning Houston | Abacus

    West Michigan Air Duct Cleaning – $239 for 12 vents cleaned … - October 24, 2016 by Mr HomeBuilder

    Air Duct Cleaning Heating and Cooling

    Water Heaters, Humidifiers, etc.

    Welcome to West Michigan Air Duct and HVAC located in Jenison, MI and serving the Grand Rapids area. We offerProfessional air duct cleaning for $239!We specialize in air duct cleaning, carpet cleaning, dryer vent cleaning, window cleaning and cleanout services. Every job starts and ends with photo inspections. We want every homeowner to be satisfied with our service so we share before and after photos so you can see what we did. Heating, ventilation and air conditioning systems collect a variety of pollutants including mold, dust and bacteria. Once the air ducts are cleaned, the air quality improves greatly. If you recently moved into a new home or if you have been in your home for a while, contact us for service!

    Air Duct Cleaning $239! Up to 12 air ducts cleaned!

    What are the benefits of air duct cleaning? Eliminate pet hair, dander and mold due to water damage. Reduce allergies and contaminants caused by smoking, construction work or fungi. Improve your home life when you improve your indoor air quality.

    Call West Michigan Air Duct and HVAC to benefit from cleaner air! Read about our services.

    Go here to see the original:
    West Michigan Air Duct Cleaning - $239 for 12 vents cleaned ...

    Air Duct Cleaning in Atlanta Kiwi Services - October 24, 2016 by Mr HomeBuilder

    Your air ducts can harbor mold, mildew and all kinds of other undesirables, and those unwelcome particulates can make their way into the air you breathe every time you turn on your air conditioner or heater. If you're living in Atlanta, there's great news: Kiwi air duct cleaning services and their 30 years of experience within the industry can help with pet dander, allergy issues and more.

    Clean air ducts mean clean, breathable air in your home. Kiwi air duct cleaning Atlanta uses high-powered, commercial-strength vacuums with fixed brushes to remove dirt and debris from your home's air ducts. That means you and your family don't have to worry about airborne contaminants polluting the air you breathe while you're at home.

    Kiwi's air duct cleaning process is incredibly thorough. Our total-system special air duct cleaning ensures that every corner of your air handling system is free from mold and mildew, as well as free from dust, dirt and debris.

    If your heating and cooling system isn't new, or if it has been exposed to humidity or moisture, you may need a professional air duct cleaning right away. Unfortunately, some Atlanta homes have heating and cooling systems that aren't installed properly; systems that are poorly put-together can harbor even more contaminants and cause more problems, so those need more frequent cleanings as well.

    Polluted air is often a direct result of moisture in your heating and cooling system. A damp environment is the ideal place for trapped dirt and debris to harbor mold and mildew.

    Moisture sneaks into your air ducts from humidity, the presence of any amount of water, and even the ordinary condensation that comes with normal temperature fluctuations. When mold grows in your air ducts, it releases tiny spores into the air; these spores travel right through your air ducts and land in your home. They can take root on your furniture, causing odors and damage, or creep down your walls and cause discoloration. Mold spores can become embedded in your carpets or get sprinkled all over your bed. Worst of all, you're breathing them in all day, every day.

    When mold spores land, they don't die. They keep growing. These difficult little spores can be the root of allergies and serious health problems.

    Clean air is best for healthy people and those with compromised immune systems; in fact, people with compromised immune systems are most vulnerable to mold sensitivity.

    Since 1987, Kiwi has been providing all sorts of cleaning services. Our expert technicians will evaluate your air duct system and choose one of many methods to perform the most in-depth cleaning. We also use antimicrobial treatments that prevent mold from taking up residence in your duct system, and we guarantee against it for two years after your service. An additional 30-day clean carpet guarantee on our services will keep you doubly safe. The end result: clean, debris-free and soot-free air ducts that can't harbor mold, mildew or dangerous bacteria. Call us at 770-573-6079 so we can help you and your family breathe easier.

    KIWI Air Duct Cleaning Atlanta, GA 30302, 30303, 30304, 31195, 31196, 39901 770-573-6079

    John M. (Atlanta, GA, 30311) "We used Kiwi for air duct cleaning twice in the past and we were very pleased with the services they provided. The technicians were knowledgeable, answered our questions about the procedures and they did a thorough job. We have invited them to our home for the third time to clean our air ducts again."

    The rest is here:
    Air Duct Cleaning in Atlanta Kiwi Services

    Air Duct Cleaning – City Carpet Cleaners - October 24, 2016 by Mr HomeBuilder

    WHAT ARE THE ADVANTAGES OF HAVING YOUR AIR DUCTS CLEANED?

    We at City Carpet Cleaners, believe that cleaning your air ducts is actually quite important, most companies and even homeowners dont understand just how important it is to having clean ducts. But what precisely is the benefit? The health benefits for the people who are currently making use of the space could be greatly improved, that is if the people are suffering allergies, in any case youre less likely to actually contract a harmful disease.

    After you hire City Carpet Cleaners youll quickly find out that there are no cleaning crews like ours, we know how to get the job done, and were considered one of Houstons most highly rated cleaners. But, were in no way healthcare specialists, and we understand that cleaning your air ducts might not affect your health in any positive way. Nevertheless, youll always have to consider if the indoor air quality is actually decreasing.

    Here is the original post:
    Air Duct Cleaning - City Carpet Cleaners

    Duct (flow) – Wikipedia - October 24, 2016 by Mr HomeBuilder

    Ducts are used in heating, ventilation, and air conditioning (HVAC) to deliver and remove air. The needed airflows include, for example, supply air, return air, and exhaust air.[1]Ducts commonly also deliver ventilation air as part of the supply air. As such, air ducts are one method of ensuring acceptable indoor air quality as well as thermal comfort.

    A duct system is also called ductwork. Planning (laying out), sizing, optimizing, detailing, and finding the pressure losses through a duct system is called duct design.[2]

    Ducts can be made out of the following materials:

    Galvanized mild steel is the standard and most common material used in fabricating ductwork because the zinc coating of this metal prevents rusting and avoids cost of painting. For insulation purposes, metal ducts are typically lined with faced fiberglass blankets (duct liner) or wrapped externally with fiberglass blankets (duct wrap). When called for, a double walled duct is used. This will usually have an inner perforated liner, then a 12" layer of fiberglass insulation contained inside an outer solid pipe.

    Rectangular ductwork commonly is fabricated to suit by specialized metal shops. For ease of handling, it most often comes in 4' sections (or joints). Round duct is made using a continuous spiral forming machine which can make round duct in nearly any diameter when using the right forming die and to any length to suite, but the most common stock sizes range evenly from 4" to 24" with 6"-12" being most commonly used. Stock pipe is usually sold in 10' joints. There are also 5' joints of non-spiral type pipe available, which is commonly used in residential applications.

    Aluminium ductwork is lightweight and quick to install. Also, custom or special shapes of ducts can be easily fabricated in the shop or on site.

    The ductwork construction starts with the tracing of the duct outline onto the aluminium preinsulated panel. The parts are then typically cut at 45, bent if required to obtain the different fittings (i.e. elbows, tapers) and finally assembled with glue. Aluminium tape is applied to all seams where the external surface of the aluminium foil has been cut. A variety of flanges are available to suit various installation requirements. All internal joints are sealed with sealant.

    Aluminum is also used to make round spiral duct, but it is much less common than galvanized steel.

    Traditionally, air ductwork is made of sheet metal which was installed first and then lagged with insulation. Today, a sheet metal fabrication shop would commonly fabricate the galvanized steel duct and insulate with duct wrap prior to installation. However, ductwork manufactured from rigid insulation panels does not need any further insulation and can be installed in a single step. Both polyurethane and phenolic foam panels are manufactured with factory applied aluminium facings on both sides. The thickness of the aluminium foil can vary from 25 micrometres for indoor use to 200 micrometres for external use or for higher mechanical characteristics. There are various types of rigid polyurethane foam panels available, including a water formulated panel for which the foaming process is obtained through the use of water and CO2 instead of CFC, HCFC, HFC and HC gasses. Most manufacturers of rigid polyurethane or phenolic foam panels use pentane as foaming agent instead of the aforementioned gasses.

    A rigid phenolic insulation ductwork system is listed as a class 1[clarification needed] air duct to UL 181 Standard for Safety.

    Fiberglass duct board panels provide built-in thermal insulation and the interior surface absorbs sound, helping to provide quiet operation of the HVAC system.

    The duct board is formed by sliding a specially-designed knife along the board using a straightedge as a guide. The knife automatically trims out a groove with 45 sides which does not quite penetrate the entire depth of the duct board, thus providing a thin section acting as a hinge. The duct board can then be folded along the groove to produce 90 folds, making the rectangular duct shape in the fabricator's desired size. The duct is then closed with outward-clinching staples and special aluminum or similar metal-backed tape.

    Flexible ducts (also known as flex) are typically made of flexible plastic over a metal wire coil to shape a tube. They have a variety of configurations. In the United States, the insulation is usually glass wool, but other markets such as Australia, use both polyester fibre and glass wool for thermal insulation. A protective layer surrounds the insulation, and is usually composed of polyethylene or metalised PET. It is commonly sold boxes containing 25' of duct compressed into a 5' length. It is available in diameters ranging from as small as 4" to as big as 18", but the most commonly used are even sizes ranging from 6" to 12".

    Flexible duct is very convenient for attaching supply air outlets to the rigid ductwork. It is commonly attached with long zip ties or metal band claps. However, the pressure loss is higher than for most other types of ducts. As such, designers and installers attempt to keep their installed lengths (runs) short, e.g. less than 15 feet or so, and try to minimize turns. Kinks in flexible ducting must be avoided. Some flexible duct markets prefer to avoid using flexible duct on the return air portions of HVAC systems, however flexible duct can tolerate moderate negative pressures. The UL181 test requires a negative pressure of 200 Pa.

    This is actually an air distribution device and is not intended as a conduit for conditioned air. The term fabric duct is therefore somehow misleading; fabric air dispersion system would be the more definitive name. However, as it often replaces hard ductwork, it is easy to perceive it simply as a duct. Usually made of polyester material, fabric ducts can provide a more even distribution and blending of the conditioned air in a given space than a conventional duct system. They may also be manufactured with vents or orifices.

    Fabric ducts are available in various colours, with options for silk screening or other forms of decoration, or in porous (air-permeable) and non-porous fabric. The determination which fabric is appropriate (i.e. air-permeable or not) can be made by considering if the application would require an insulated metal duct. If so, an air-permeable fabric is recommended because it will not commonly create condensation on its surface and can therefore be used where air is supplied below the dew point. Material that eliminates moisture may be healthier for the occupants. It can also be treated with an anti-microbial agent to inhibit bacterial growth. Porous material also tends to require less maintenance as it repels dust and other airborne contaminants.

    Fabric made of more than 50% recycled material is also available, allowing it to be certified as green product. The material can also be fire retardant, which means that the fabric can still burn, but will extinguish when the heat source is removed.

    Fabric ducts are not rated for use in ceilings or concealed attic spaces. However, products for use in raised floor applications are available. Fabric ducting usually weighs less than other conventional ducting and will therefore put less stress on the building's structure. The lower weight allows for easier installation.

    Fabric ducts requires a minimum of certain range of airflow and static pressure in order for it to work.

    The finish for external ductwork exposed to the weather can be sheet steel coated with aluminium or an aluminium/zinc alloy, a multilayer laminate, a fibre reinforced polymer or other waterproof coating.

    Besides the ducts themselves, complete ducting systems contain many other components.

    A duct system often begins at an air handler. The blowers in the air handler can create substantial vibration, and the large area of the duct system would transmit this noise and vibration to the inhabitants of the building. To avoid this, vibration isolators (flexible sections) are normally inserted into the duct immediately before and after the air handler. The rubberized canvas-like material of these sections allows the air handler to vibrate without transmitting much vibration to the attached ducts. The same flexible section can reduce the noise that can occur when the blower engages and positive air pressure is introduced to the ductwork.

    Downstream of the air handler, the supply air trunk duct will commonly fork, providing air to many individual air outlets such as diffusers, grilles, and registers. When the system is designed with a main duct branching into many subsidiary branch ducts, fittings called take-offs allow a small portion of the flow in the main duct to be diverted into each branch duct. Take-offs may be fitted into round or rectangular openings cut into the wall of the main duct. The take-off commonly has many small metal tabs that are then bent to attach the take-off to the main duct. Round versions are called spin-in fittings. Other take-off designs use a snap-in attachment method, sometimes coupled with an adhesive foam gasket for improved sealing. The outlet of the take-off then connects to the rectangular, oval, or round branch duct.

    Ducts, especially in homes, must often allow air to travel vertically within relatively thin walls. These vertical ducts are called stacks and are formed with either very wide and relatively thin rectangular sections or oval sections. At the bottom of the stack, a stack boot provides a transition from an ordinary large round or rectangular duct to the thin wall-mounted duct. At the top, a stack head can provide a transition back to ordinary ducting while a register head allows the transition to a wall-mounted air register.

    Ducting systems must often provide a method of adjusting the volume of air flow to various parts of the system. Volume control dampers (VCDs; not to be confused with smoke/fire dampers) provide this function. Besides the regulation provided at the registers or diffusers that spread air into individual rooms, dampers can be fitted within the ducts themselves. These dampers may be manual or automatic. Zone dampers provide automatic control in simple systems while variable air volume (VAV) allows control in sophisticated systems.

    Smoke and fire dampers are found in ductwork where the duct passes through a firewall or firecurtain.

    Smoke dampers are driven by a motor, referred to as an actuator. A probe connected to the motor is installed in the run of the duct and detects smoke, either in the air which has been extracted from or is being supplied to a room, or elsewhere within the run of the duct. Once smoke is detected, the actuator will automatically close the smoke damper until it is manually re-opened.

    Fire dampers can be found in the same places as smoke dampers, depending on the application of the area after the firewall. Unlike smoke dampers, they are not triggered by any electrical system (which is an advantage in case of an electrical failure where the smoke dampers would fail to close). Vertically mounted fire dampers are gravity operated, while horizontal fire dampers are spring powered. A fire damper's most important feature is a mechanical fusible link which is a piece of metal that will melt or break at a specified temperature. This allows the damper to close (either from gravity or spring power), effectively sealing the duct, containing the fire, and blocking the necessary air to burn.

    Turning vanes are installed inside of ductwork at changes of direction (e.g. at 90 turns) in order to minimize turbulence and resistance to the air flow. The vanes guide the air so it can follow the change of direction more easily.

    Plenums are the central distribution and collection units for an HVAC system. The return plenum carries the air from several large return grilles (vents) or bell mouths to a central air handler. The supply plenum directs air from the central unit to the rooms which the system is designed to heat or cool. They must be carefully planned in ventilation design.[why?]

    While single-zone constant air volume systems typically do not have these, multi-zone systems often have terminal units in the branch ducts. Usually there is one terminal unit per thermal zone. Some types of terminal units are VAV boxes (single or dual duct), fan-powered mixing boxes (in parallel or series arrangement), and induction terminal units. Terminal units may also include a heating or cooling coil.

    Air terminals are the supply air outlets and return or exhaust air inlets. For supply, diffusers are most common, but grilles, and for very small HVAC systems (such as in residences) registers are also used widely. Return or exhaust grilles are used primarily for appearance reasons, but some also incorporate an air filter and are known as filter returns.[3]

    The position of the U.S. Environmental Protection Agency (EPA) is that "If no one in your household suffers from allergies or unexplained symptoms or illnesses and if, after a visual inspection of the inside of the ducts, you see no indication that your air ducts are contaminated with large deposits of dust or mold (no musty odor or visible mold growth), having your air ducts cleaned is probably unnecessary."[4] A thorough duct cleaning done by a professional duct cleaner will remove dust, cobwebs, debris, pet hair, rodent hair and droppings, paper clips, calcium deposits, children's toys, and whatever else might collect inside. Ideally, the interior surface will be shiny and bright after cleaning. Insulated fiber glass duct liner and duct board can be cleaned with special non-metallic bristles. Fabric ducting can be washed or vacuumed using typical household appliances.

    Duct cleaning may be personally justifiable for that very reason: occupants may not want to have their house air circulated through a duct passage that is not as clean as the rest of the house. However, duct cleaning will not usually change the quality of the breathing air, nor will it significantly affect airflows or heating costs.

    Cleaning of the duct system may be necessary if:

    In commercial settings, regular inspection of ductwork is recommended by several standards. One standard recommends inspecting supply ducts every 12 years, return ducts every 12 years, and air handling units annually.[5] Another recommends visual inspection of internally lined ducts annually[6] Duct cleaning should be based on the results of those inspections.

    Inspections are typically visual, looking for water damage or biological growth.[5][6][7] When visual inspection needs to be validated numerically, a vacuum test (VT) or deposit thickness test (DTT) can be performed. A duct with less than 0.75mg/100m2 is considered to be clean, per the NADCA standard.[7] A Hong Kong standard lists surface deposit limits of 1g/m2 for supply and return ducts and 6g/m2 for exhaust ducts, or a maximum deposit thickness of 60m in supply and return ducts, and 180m for exhaust ducts.[8] Another UK standard recommends ducts cleaning if measured bacterial content is more than 29 colony forming units (CFU) per 10cm2; contamination is classified as "low" below 10 CFU/cm2, "medium" at up to 20 CFU/cm2, and "high" when measured above 20 CFU/cm2.[9]

    Air pressure combined with air duct leakage can lead to a loss of energy in a HVAC system. Sealing leaks in air ducts reduces air leakage, optimizes energy efficiency, and controls the entry of pollutants into the building. Before sealing ducts it is imperative to ensure the total external static pressure of the duct work, and if equipment will fall within the equipment manufacturer's specifications. If not, higher energy usage and reduced equipment performance may result.

    Commonly available duct tape should not be used on air ducts (metal, fiberglass, or otherwise) that are intended for long-term use. The adhesive on so called duct tape dries and releases with time. A more common type of duct sealant is a water-based paste that is brushed or sometimes sprayed on the seams when the duct is built. Building codes and UL standards call for special fire-resistant tapes, often with foil backings and long lasting adhesives.

    Signs of leaky or poorly performing air ducts include:

    More here:
    Duct (flow) - Wikipedia

    « old entrysnew entrys »



    Page 13«..10..12131415..2030..»


    Recent Posts