Rooftop HVAC equipment: this article describes rooftop mounted HVAC systems - rooftop air conditioners, rooftop heat pumps, and rooftop heating equipment. We describe types of roof-mounted HVAC equipment and common inspection points, operating problems, and repair approaches. At page top is a roof mounted swamp cooler or evaporative cooling system on a private home in Tucson. Rooftop mounted central air conditioning systems may include both the cooling unit (evaporator coil, blower fan, filters) and the compressor/condenser unit in one package. At above right is a complex of roof-mounted AC/heat pump systems on a Christchurch, New Zealand high rise building roof. These units may be a bit crowded as well as blown-on by the building's ventilation system openings at the upper right of the image. At above left is a flat-roof mounted commercial cooling system located in New York. Rooftop mounted central cooling systems may be smaller packaged systems which blow their cool air down directly into the cooled space through an opening in the roof, drawing return air from a nearby location, or

the rooftop cooling system may be connected to duct work which in turn blows down into multiple building areas to deliver cool air, drawing return air from one or more centralized returns. In many commercial installations, the entire area over a suspended ceiling may serve as one giant return plenum through which pass the supply ducts, delivering air to individual supply registers. While the list above describes the common components of a typical residential air conditioning system,air conditioning unit energy credit other configurations and packaged units are also in increased use in both residential and commercial installations.20 ton cooling unit Alternative HVAC designs may combine all components except for the duct work in a rooftop mounted unit such as3 ton gas heating and air conditioning systems

the one shown above where it was mounted on a flat roof over offices at a commercial building. The outdoor compressor/condenser unit of split-system air conditioners and heat pumps is also commonly mounted on rooftops, especially flat or low-slope roofs such as the unit shown at left. Installation requirements for rooftop-mounted split system compressors / condenser units include both a service disconnect (circled in our photo) and often additional measures to assure that the unit is properly padded to avoid damage to the roof membrane, and to assure that the unit is properly levelled. IN our OPINION, where rooftop mounted split system condenser units are exposed to high temperatures system operating efficiency and costs may be affeted. Details are at SPLIT SYSTEM AIR CONDITIONERS & HEAT PUMPS These photographs show what happens when a rooftop packaged-terminal air-conditioning air handler (PTAC) and horizontal runs of air-ducts are installed on a roof surface and when that air duct system is improperly sealed and

also is lined with fiberglass insulation. Water ponded on the old, concave sections of air conditioning ducts on the roof of this commercial office space. As water leaked into the duct system it saturated fiberglass duct liner which in turn, had its normal coating of organic dust and debris from the building, risking an indoor mold or pathogen problem for some of the occupants. The cure for these duct leaks was costly: it was determined that it was less costly to completely replace the rooftop ducts with new metal ducts using outside insulation than it would have been to remove the contaminated fiberglass liner, clean the existing ducts, repair the leaks, and insulate theirThe work was combined with other building HVAC cleaning and repairs. Common inspection points & functional issues around rootop-mounted HVAC equipment include: Shown at left, support system for rooftop air conditioners / heat pumps mounted on a metal roof in Christchurch, New Zealand.

Continue reading at SPLIT SYSTEM Ductless Air Conditioners or select a topic from the More Reading links or topic ARTICLE INDEX shown below.The Sikorsky helicopter hovered over Dickson County High School multiple times Friday afternoon.The campus was closed as the large aircraft, owned by Solley Equipment & Rigging of Nashville and Decatur, Ala., loaded new HVAC units on to the school’s roof as part of a comprehensive HVAC system overhaul.Solley, which was hired by the contractor for the HVAC replacement, Blaylock Construction, of Lewisburg, made 10 lifts to set the new units into place.The process was delayed from the expected 7 a.m. start time until about noon due to morning fog and overcast conditions, according to Dickson County Schools Maintenance Director Gerald Clifton.Work on the school’s HVAC system will continue after the unit placement, though the bulk of the work will be scheduled around non-class hours, according to school leaders. THE TENNESSEANHelicopter to lift HVAC units at Dickson Co. HighMOST POPULAR STORIESWomen charged after children found naked, dirty in Cross PlainsPolice: Man shot, killed in act of 'road rage'Dansby Swanson living Braves dream while living at homeStudent with gun planned to shoot teachers, counselor talked him downBCBST shakeup brings uncertainty to many in Tennessee

891 posts, read 1,761,932 times Hey there Albuquerque, my wife and I visited last year and while looking over photos from the trip we always ask each other the same question - why so many rooftop HVAC units on the suburban homes? We're from the east coast and had never seen anything like that except on commercial buildings or downtown row houses. Everyone here has their HVAC units beside the house on the ground... ...anyways can anyone here solve this argument for us? We advance all kinds of theories to each other but have never found anything online to tell us one way or another. It's gotta be more expensive and slightly more complicated roof-wise to put them up there, so what's the advantage? Naive folks from the east are wondering... 384 posts, read 931,943 times Originally Posted by trappedinNMThank you so much, that explains tons - kind of like those bazooka things people used to mount to car windows (especially VW bugs) way back in the day before automotive compressors were commonplace.

Makes a lot of sense now that you mention it. There are some uses of those here in large commercial greenhouse settings but we didn't even know that sort of thing existed in a little residential unit. Sounds a lot more power-efficient than just a compressor alone (or like a great substitute for days when you can get away with it). 3,057 posts, read 9,591,035 times Originally Posted by khyron Yeah, khyron, if you do a google search under "swamp coolers" or "evaporative coolers", you'll find a ton of interesting information on them. They are pretty much only effective when the humidity levels are well below 35%, so they are really only utilized in desert cities like Albuquerque, or semi-arid cities like Santa Fe and even Denver a bit. You'll find them commonly in other cities like El Paso, TX and somewhat in lower desert cities like Tucson, AZ Phoenix, AZ and Las Vegas, NV however, the swamp coolers really only cool the inside of the house by about 20 degrees to the air on the outside, so with cities like Phoenix routinely clocking in at over 110+ degrees in the summertime