The mechanical systems of Scaife Hall in 1961 were much different from today. There were three heating and air conditioning units serving the whole building. The mechanical room was located on the basement floor where two heating & AC units were installed. The #1 heating & AC unit was dedicated to the conditioning work of the basement, ground floor, first floor and second floor spaces, while the #2 heating & AC unit served the nearby Lecture Hall on the first floor. For the third floor, there was a penthouse beyond it, which was equipped with the #3 heating & AC unit to serve the third floor. The most significant feature of the mechanical systems in 1961 was the implementation of dual-duct air mixing boxes to control and handle indoor air. All air cells shown on the drawings were in the floor construction above. The ceiling of this floor was used to serve the air mixing boxes on the floor above. Besides the regular internal air supply outlet, there were a set of sill treatment units installed along the building envelope to control the peripheral air temperature.

The air to the window sill treatment shall be supplied from the air mixing boxes at the ceiling below. The renovation in 1995 removed all the dual-duct air mixing box and implemented a new central air conditioning system. The first floor applied a window air distribution system and fan coil units were installed below the windows on the second and third floor. For the fourth floor a plenum air return approach was also implemented. Same as in the 1961, air handling units located in the mechanical room served the basement, first, second and third floor spaces while another air handling unit in the penthouse served the fourth floor. On each of the floors, there was an exhaust air duct that could help discharge the exhausted air from the restrooms. In addition, a reheat system was implemented for the basement and a reheat/recool system was established on the fourth floor. The most up-to-date renovation of the mechanical systems of Scaife Hall was finished in 2004. The HVAC systems for the basement and the first floor were totally redesigned and for the second to fourth floor, designers modified the existing ducts, pipes and diffusers by rearranging them.

After renovation in 2004, conditioned air for the basement and the first floor comes from air handling units located in the mechanical room with a heat recovery system while the penthouse is responsible for the second to fourth floor spaces. In particular, the second to fourth floor remained all the features of renovation in 1995 except for some changes in the distribution of ducts and diffusers. motor home ac unitHowever, for the basement, a total five reheat units were added, which resulted in the change of pipes and ducts correspondingly. how much to replace outside ac unitAs for the first floor, a floor plenum air supply coupling with a ceiling plenum air return system were introduced.how long does it take to charge an ac unit

It is also notable that the air supplied by the duct is just for ventilation purpose and fan coil units take responsibility to undertake the thermal loads. The reason why duct works were sometimes overlapping and too complex is that designers would like to utilize the old duct work to reduce cost. Also, there is no ventilation in the stairwell areas. © Copyright © 2014. ALTHOUGH this area has had only a small taste of hot weather thus far this year, no one doubts that there are plenty of hot and humid days and nights still ahead - days and nights when those who own air conditioners will have their machines running full blast in bedrooms and living areas in order to lower the temperature and reduce humidity. For those who have central air conditioning all rooms will be equally comfortable, but for those who have only a single window-mounted or through-the-wall air conditioner in the bedroom, the tendency is to move into that room early in the evening because the other rooms will be quite uncomfortable by comparison.

Yet, except on the very hottest days, many of these room air conditioners can be used to help cool adjacent rooms as well because most have more cooling capacity than is needed for just that one room. One reason is that most people have a tendency to buy units that are oversized for the actual room they will be used in (often on the advice of the salesman who sold them the unit). That is why a single room air conditioner can often be used to also help cool an adjacent room, particularly on days when temperatures are only moderately hot (high 80's or low 90's), or when only one of the rooms is in use at the time. For example, a large unit located in the bedroom could be used to help cool an adjacent den or living room during the evening before you go to bed, then used only to cool the bedroom when you actually retire. Unfortunately, cool air from one room won't easily spread to the next room by itself, so just leaving the door open between the two rooms won't do the trick.

The air has to be helped along with a fan of some kind. Theoretically you could do this with one or two floor fans, positioned so they blow from the room where the air conditioner is located into the adjacent room where you want some of the cooled air to go. However, this is not always convenient or effective, and it often requires standing the fan right in the doorway or a connecting archway where people are likely to stumble over it. A much better method is to install a permanent fan as shown in the accompanying drawing. The one illustrated here is a typical exhaust fan such as is normally installed in a kitchen to expel cooking odors and smoke. A larger attic exhaust fan could also be used if the rooms involved are large and if there is enough wall space available. The fan can be installed above a doorway as shown here, or anywhere in the wall separating the two rooms. Since cold air settles, some feel that for maximum effectiveness it is probably best to install the exhaust fan down near the floor, but then the cooled air entering the other room would tend to remain near the floor.

Blowing colder air into the ''hot'' room near the ceiling will set up a more natural circulation of air in that room. As a rule, installing the fan is not a particularly difficult carpentry job. Start by first using a stud finder to locate where the studs are over the door, then install the fan between two studs so you won't have to cut any. Installing the fan right next to one of the studs is best; that way you can fasten the fan's housing to that stud. If you can't locate the studs, then trying drilling some small exploratory holes first. After determining where the studs are, carefully cut away the gypsum board or plaster to expose them. Try to cut your opening no larger than is needed for the fan housing. If the hole is too big you can easily patch it after the fan is installed, or molding can be used to create a small frame around the fan housing and to cover up jagged edges or any other irregularities in the opening. On the exhaust side of the fan (where you cut through the plaster or wallboard on the other side) you should install a louvered grill or exhaust vent of the kind normally used with air conditioners.

This will allow you to adjust the direction of the air flow so you have some control over it as it comes out into the other room. To supply power for the fan, it is best to have an electrician wire the motor permanently into a nearby wall switch. In lieu of this you can also wire the motor terminals to a sturdy extension cord that is then plugged into a convenient electrical outlet on the same wall. In those cases where you want to move cold air into a room that is not directly adjacent to the one where the air conditioner is located, it is sometimes practical to add a short length of duct work to the exhaust side of the fan to carry the air to the room where it is needed. However, if you do this, remember to keep such duct work straight, or with slight curves only, and as short as possible. Most small exhaust fans do not have the ability to move quantities of air through a great deal of duct work, especially if there are any bends or elbows involved. One side-advantage to an air-moving installation of this type is that it can also be used for moving warm air in the winter - for example, when there is a fireplace or wood-burning stove in one room and you would like to spread some of this warmth around to adjacent rooms.