The requested URL /LT_Maint.html was not found on this server. Choose from the categories below to find the best rooftop solution for your needs. Rebel® Cooling & Heat Pump 3 to 28 tons 15 to 75 tons RoofPak® Heating & Cooling 15 to 140 tons RoofPak® Evaporative Cooled Heating/Cooling 75 to 150 tons Maverick® I Cooling & Heat Pump 3 to 25 tons Models DC Cooling & Heat Pump 3 to 20 tons Remember that article I wrote about ducts installed against the roof deck and how I said it was probably the absolute worst single location for installing ducts?  Well, in the comments, Dave Roberts, a senior engineer at the National Renewable Energy Lab (NREL), wrote about a paper he co-authored last year and included a link to it. Up against the deck may be the worst place in the attic to install ducts, but Roberts shows that putting them in the attic at all is the worst place in the house you can install ducts. The report, Ducts in the Attic?

What Were They Thinking?, summarizes the research that's been done about putting ductwork in unconditioned attics and basically says it's about the stupidest thing we do in homes that do a lot of air conditioning. I encourage you to download and read this report. central ac unit freezing overIf you're building or remodeling a home, make sure the general contractor (if it's not you) and the HVAC contractor get copies.portable ac floor unit I love the analogy they use to introduce one of the main problems with this location. 30 ton hvac unit price"Heat exchangers," they write, "are designed to transfer as much heat as possible from one fluid to another." Comparing this configuration to a solar water heater, they make the case that putting air conditioning ducts in a hot attic is an effective way to heat up the conditioned air as it travels from the air handler to the conditioned space inside the home.

If you've studied heat transfer at all, you may recall that the rate at which heat moves from a warmer to a cooler body depends on the temperature difference, which we abbreviate as ΔT. An attic can get up to about 130° F in the summer, and the conditioned air entering the ducts is about 55° F or so. With hundreds of square feet of ductwork surface area in the attic and a ΔT of 75° F, the air coming out of the vents in your home will be significantly higher than 55° F. Throw duct leakage into the mix, and the problems are even worse. What Roberts and his co-author Jon Winkler did, in addition to reviewing the literature about this topic, was to model the savings possible when you relocate the ducts from an unconditioned attic to the conditioned space inside the building envelope. They chose Houston, Phoenix, and Las Vegas as the locations for their modeled houses. The table below summarizes the main results. In addition to comparing ducts in the attic to ducts inside the building envelope, Roberts and Winkler also looked at electricity savings of other measures, such as adding insulation, installing better windows, and using higher efficiency air conditioners.

The table below shows that moving the ducts inside is the first thing you should do to save the amount of electricity you use. In addition to saving on air conditioning operating costs, the upfront cost of cooling equipment is lower in efficient homes. Roberts and Winkler looked at moving the ducts inside compared to other building envelope improvements, and again, moving the ducts inside beats all the other methods for achieving this objective, as shown below. This report, which the authors delivered at the ACEEE (American Council for an Energy Efficient Economy) Summer Study in August 2010, shows definitively that putting ducts in attics in cooling dominated climates is a practice that needs to end. Download the paper here: Ducts in the Attic? What Were They Thinking?Do you know what type of heating system you have in your home? considered this knowledge unnecessary in the past, take into account that learning about your current heating system and properly maintaining it

can extend its life, lower your heating costs, and ensure your family stays comfortable throughout the cold of the season. helpful information from our heater repair experts at Aire Serv®. Sometimes referred to as forced air systems, these heating systems burn natural gas, propane, oil, or use electricity to heat your home, and are the most commonly used heating systems. Air is heated in the furnace and then distributed throughout your house via ductwork. found in closets, basements, crawlspaces, and attics. There are many concerns when deciding whether to choose a gas, oil, or electric furnace. can help you make this difficult decision. Used in moderate climates, heat pumps offer both heating and cooling capabilities. Working like your refrigerator, they use electricity to move heat from a cool space to a warm space, depending on the season. typically split, with both an indoor cabinet as well as an outdoor metalMost systems work by moving air through ducts;

however, ductless versions are available. Geothermal heat pumps use the naturally consistent temperature of the earth to heat or cool the air in your home or business. They are known for being quiet and incredibly energy efficient, with drawbacks including the relatively high upfront cost and the potential disruption to your existing landscaping Boilers are made of two parts: Boilers typically have pressure gauges, and may use electricity, natural gas, propane, or oil to operate. Heat created from hot water or steam is used to heat your home and may be distributed through baseboard radiators, radiant heat floor systems, or heating air via a coil. provide hot water to your home in addition to heat. Packaged units may be either electric or gas, and combine all system components into one cabinet which is typically found on a slab next to your home or on the roof. These systems combine both heating and cooling capabilities,

eliminating the need for a separate furnace indoors. to the system through the roof or exterior wall and distributes heat or air throughout your home. The location of your heating system will vary depending on the type of system in your home. If you are having difficulty locating your heating system and your system uses ductwork, try following the ductwork to itsIf you are inexperienced, it is in the best interest of your safety to look with your eyes and not with your hands. Regardless of your level of experience, be sure to enlist the help of an expert when servicing your heater and ask them how to properly handle routine maintenance for your particular model during the service call. Numerous reports are made every year to the Consumer Product Safety Commission resulting from incidents occurring with heating and air conditioning units such as electrocution, lacerations, cuts, bruises, strains, and sprains. For help determining what type of heating system your home uses, contact