Must operate on 120 volt (standard house outlet) Must not be larger than 10,000 BTUs Must be in good, safe operating condition, including cord Must be designed so an exterior support brace is not needed Must fit within the window size opening listed below for the proper residence hall Bergstrom: 28 1/2" width by 20 3/4" height Madelaine/Lorraine: 24" width by 24" height Mary Minahan McCormick: 20 3/4" width by 18 1/2" height Victor McCormick: 20" width by 21" height Burke: 17" width by 29 1/4" height Sensenbrenner: 40 3/4" width by 23 3/4" height (double unit) 17" width by 23 3/4" height (triple unit) College Houses: Handled on a case-by-case basis All window air conditioners will be installed and removed by SNC staff only and any window air conditioner not installed by SNC staff will be removed. SNC is not responsible for maintenance or repair of personal A/C units. A two-week notice is required for installation or removals.

By filling out the form below, you are requesting permission to have an air conditioning unit installed in your residence at St. Norbert College. Understanding that air conditioners are only allowed when a medical need exists, you have met with Academic Support Services for the proper documentation. 12 ton ac unit costYou understand that there is a charge of $175 per academic year. outside ac unit filterThis charge covers installation, removal and electricity. ac unit burnedYou are responsible for the payment of this charge and for providing the air conditioning unit, within the guidelines provided by the facilities department. Air Conditioner Request Form Do you have a medical accommodation approved through Academic Support Services? You are hereHome » Building Design » Active HVAC Systems » HVAC Controls and Operations

Simulation CFD: Detailed Heat Transfer and Fluid Flow AnalysisAs with all air conditioning systems the principle remains the same whereby the heat is removed from one area and replaced with chilled dry air and the hot air is expelled, normally to the outside atmosphere. As you can see from this typical example of a air conditioning system, the ambient air is drawn over the condensor that can best described as a ‘radiator’ as seen on motor vehicles but instead of water running through the system it contains a refrigerant gas. On its journey around the system it has three main stages; the evaporator contains the sub-cooled refrigerant and air blows through its veins to release the chilled dry air into the room, the condenser contains the high temperature gas that once again air is blown through the veins collecting the heat as it passes through and this is then expelled outside. An air conditioner is able to cool a building because it removes heat from the indoor air and transfers it outdoors.

A chemical refrigerant in the system absorbs the unwanted heat and pumps it through a system of piping to the outside coil. The fan, located in the outside unit, blows outside air over the hot coil, transferring heat from the refrigerant to the outdoor air. Most air conditioning systems have five mechanical components: • an evaporator coil • a chemical refrigerant Most central air conditioning units operate by means of a split system. That is, they consist of a ‘hot’ side, or the condensing unit—including the condensing coil, the compressor and the fan—which is situated outside your home, and a ‘cold’ side that is located inside your home. The cold side consists of an expansion valve and a cold coil, and it is usually part of your furnace or some type of air handler. The furnace blows air through an evaporator coil, which cools the air. Then this cool air is routed throughout your home by means of a series of air ducts. A window unit operates on the same principal, the only difference being that both the hot side and the cold side are located within the same housing unit.

The compressor (which is controlled by the thermostat) is the ‘heart’ of the system. The compressor acts as the pump, causing the refrigerant to flow through the system. Its job is to draw in a low-pressure, low-temperature, refrigerant in a gaseous state and by compressing this gas, raise the pressure and temperature of the refrigerant. This high-pressure, high-temperature gas then flows to the condenser coil. The condenser coil is a series of piping with a fan that draws outside air across the coil. As the refrigerant passes through the condenser coil and the cooler outside air passes across the coil, the air absorbs heat from the refrigerant which causes the refrigerant to condense from a gas to a liquid state. The high-pressure, high-temperature liquid then reaches the expansion valve. The evaporator coil is a series of piping connected to a furnace or air handler that blows indoor air across it, causing the coil to absorb heat from the air. The cooled air is then delivered to the house through ducting.

The refrigerant then flows back to the compressor where the cycle starts over again. The most important maintenance task that will ensure the efficiency of your air conditioner is to routinely replace or clean its filters. Clogged, dirty filters block normal airflow and reduce a system’s efficiency significantly. With normal airflow obstructed, air that bypasses the filter may carry dirt directly into the evaporator coil and impair the coil’s heat-absorbing capacity. Filters are located somewhere along the return duct’s length. Common filter locations are in walls, ceilings, furnaces, or in the air conditioner itself. Some types of filters are reusable; others must be replaced. They are available in a variety of types and efficiencies. Clean or replace your air conditioning system’s filter or filters every month or two during the cooling season. Filters may need more frequent attention if the air conditioner is in constant use, is subjected to dusty conditions, or you have fur-bearing pets in the house.