by admin | Aug 18, 2014 | National Air Warehouse
Determining the right size air conditioning unit for your home can help you to have trouble-free climate control without frequent breakdowns and shortened lifespan. Bigger is not necessarily better in air conditioning, and the right unit will help you to save money and frustration as time goes on. Although a number of “rules of thumb” exist for choosing the right size unit, other factors may also be involved in efficient air conditioning operation.
House and Room Size
Careful measurements of the size of the house and each individual room must be done to determine the square area that is to be climate controlled. Although you may think that having more air conditioning capacity than is required by the house, the wrong size unit will cause greater wear and tear on parts.
Ceiling Height
The ceiling height in your home will have a significant effect on the amount of wear on the unit. A unit will have to work harder to fill the space in a room with a higher ceiling than standard height. Sloped ceilings may require increased operation than standard height ceilings.
House Wall Area
The exposed wall space on each side of the building exterior will also have an effect on air conditioning sizing. The number of doors and windows that allow air leakage is calculated into the number of BTU’s needed to cool interior areas.
Type of Construction
The type of construction of your home can affect how the air conditioning system operates. Factors such as the location of the unit, the length of ductwork, type of connections and number of floors in the home will affect the efficiency of operation of the unit.
Insulation Level in the Home
Many newer homes have a high level of insulation of attics, windows, doors, basements and other areas. The ability to keep cool air in the structure will also factor in the size of the air conditioning unit you choose.
The Home’s Air Leakage Rate
The home’s air leakage rate will also factor in the size of the air conditioning unit. How well windows and doors fit, the amount of caulking to seal air leaks and the condition of certain construction features can make a significant difference in how much cool air escapes from the interior and how hard the unit must work to replace it.
The Home’s Duct Leakage Rate
A professional heating and air conditioner contractor will have the equipment necessary for measuring the amount of leakage in the home’s ductwork.
All of these factors can be computed by a professional heating and air conditioning contractor to ensure that you have the right size air conditioning unit for efficient operation in your home. A trained technician can perform a Manual J, D, T and S to properly design and measure the right amount of cooling and heating that your home needs. You can learn more about the Manual calculations if you click here. If you would like additional information on sizing you current or new AC system, please call one of our friendly staff to help guide you on determining the correct AC system size.
by admin | Aug 12, 2014 | National Air Warehouse
Insulated flexible ducts with metalized jackets are used in the HVAC industry for supply air, return air, and exhaust air transport where air conditioners, heaters, and ventilation applications exist. Such ductwork maintains good air quality, comfort, and prevents costly inefficiency. The inner polyethylene tube with reinforced wire coil gives strength and keeps the air inside the tube. The thin metal jacket keeps moisture and condensation from getting on the insulation, and the flexibility allows the duct to curve if necessary. The insulation in U.S. insulated ducts is typically glass wool or fiber glass.
The size of the fitting on the heater, AC unit, etc. will of course determine the needed duct diameter, and the length is normally cut by the installer. It is ideal to keep the distance short since a certain amount of pressure will be lost by air while it is travelling through the duct, and sharp bends and kinks also are avoided. The flexible ducts attach to the rigid sheet metal ductwork, to the AC, the heater, or have open contact with outside air.
Each duct has an “R” rating for its insulating capacity- for example, R6 ducts do well up to 200 degrees, and has one third more insulation around it than an R4. The greater insulation, the greater efficiency, but also the more one pays for the product. Wherever relatively hot air is present in the duct, especially if traveling through space with extremely lower temperature air in it, it is most important to have a high R rating. The cold air return to a heater would not need as great an R value then as the supply duct. The opposite would be the case with a split AC unit since the hot air is traveling outside, and the cold air is moving into the building. Another possible application for a high R duct would be a clothes dyer exhaust tube.
While the metal jacket keeps out moisture, there are also versions of metalized jackets, e.g. one line of ducts’ “silver jacket” feature, that are effective in noise absorption
as well. Clearly these would be more crucial when the duct goes through or near oft-used rooms- not so much in a little visited basement on the other hand.
Another special flexible duct is one with a heavy black jacket of polyethylene and UV light elements built in. They are commonly referred to as mobile home ducts for their due to their increased usage for this type of construction. This duct is particularly suited for use outside, though if in a well-lighted room, it could be useful indoors as well.
Insulated flexible ducts with metal jackets come in numerous standard sizes for different sized heater, vents, and ACs- some are even designed specifically for mobile homes. They install easy enough over round or oval fittings and can be easily cut and taped if one has the right equipment and a little experience. However, choosing the right R level for each duct and looking for special metal coatings that resist fire better or reflect light better, etc. often requires professional advice or services.
by admin | Jul 18, 2014 | National Air Warehouse
In simple terms, a gas furnace is an indoor unit designed to circulate warm air (heated within the furnace) or cool air (generally taken from an outdoor unit) throughout a home. A gas furnace contains the following main components: a burner, a heat exchanger, ductwork, and a flue or vent pipe. This article will detail these main components and where they are located within a furnace.
The burner component of a gas furnace is a heating element that warms the gas entering the furnace. Usually located at the bottom of the unit (although occasionally located on the sides), the burner uses a small flame normally ignited with a pilot light. In modern furnaces, pilot lights are ignited automatically, much like an automobile’s spark plugs.
Heat exchangers look similar to metal snakes that extend upwards from the burner. This component takes the warm air created below and transfers it to the heat distribution system (duct work). Heat exchangers are crucial to a furnace’s functionality as they integrate the heat with the air that’ll be sent throughout the home. When a homeowner has their furnace inspected, it’s important to locate the exchanger and check for any cracks or leaks as these can lead to a furnace running less efficiently.
The ductwork component of a gas furnace is the system that distributes air throughout a home. Beginning at the top of a furnace, ductwork is composed of sheet metal or plastic tubing that extends from the furnace and continues throughout the home, thus bringing air to different locations within a home. Ducts must be inspected and cleaned regularly as a clogged duct can restrict the flow of air. Mold or other contaminants can also build up within ductwork, causing serious safety issues for home occupants.
Flue pipes or vent pipes are a vital component of gas furnaces, as they take the byproducts produced through combustion and expel them from the home. The flue pipe is a larger metal tube that extends out of the furnace and leads to a vent on the exterior of a home. It is important that a flue is installed correctly to ensure that hazardous materials will not escape. Furnace vents should be checked along with a regular furnace inspection.
Gas furnaces are an efficient way to warm and cool a home. It is recommended to be familiar with a unit’s main components, as well as inspecting it regularly. This will ensure that a gas furnace is operating safely and adequately, protecting a home’s occupants while keeping energy costs low.
