In 1902, when Norwood Hall started construction, HVAC consisted of large windows for cooling and ventilation and wood or coal burning stoves for heating. In 1927, when the first large renovation of Norwood Hall took place the current system of steam radiators for heat was installed. For many years there was no change to the HVAC systems, only minimal maintenance.

Air conditioning was introduced to Norwood Hall with the creation of window units. Much of the space was cooled by numerous units blanketing the exterior walls. In 1987 much of the space was renovated to be cooled by a split duct system installed in a new drop ceiling. Only a few window units were left in places where it was not cost efficient to replace them.
Below, several of the criteria necessary to evaluate the current system have been outlined.

Use of Building
The use of a building must be considered when selecting the HVAC system so that the appropriate loads are considered for the sizing. For example, a classroom, where many students are constantly coming in and out of a relatively small space, will have much larger cooling loads than an office, where fewer people will be moving, in a more open space. This building is used primarily for offices with a few classrooms and labs.

Location of Building
Building location will obviously determine the systems used in response to the climate of the region. In central Missouri there is a large climate variance from 100ºC + in the summer to below zero in the winter. With this range both a heating and cooling element must be present in a building.

Expandability
Since Norwood Hall is a historic building, expandability is not a large concern.

Local Temperature Control
With so many systems in place local temperature control will depend upon what time of year it is, and what part of the building you are in. Each radiator has its own thermostat, allowing for much control over each unit, but units are only located on the exterior walls. Traditional the exterior rooms will be a little too warm to keep the interior rooms comfortable. So while there is much temperature control in the exterior rooms, the interior rooms are at the mercy of their neighors.
The split duct air conditioners have more local temperature control, typically having three thermostats for each section of the building they cool. Rooms where window units are still in place have 100% local temperature control.

Noise
With much of the large equipment located outside or another building the systems run quietly most of the time. The radiators may produce intrusive sounds when there is a maintenance problem, and the window units will have a low hum while the fan is running.

Heating / Cooling Loads
Load will vary by time of year and section of the building. While summer traditionally produces the largest loads, many of the high occupancy spaces will be empty while students are away for summer break. During spring and fall, when high temperature may be reached and students are on campus, should produce the largest loads, while winter produces the least with much body heat to keep the building warm.
Heating
Heating is controlled by steam radiators place along the exterior walls and in stairwells. The steam is produced by five large boilers ran by the campus power plant. The steam is then piped to the building by a main line in the underground utility tunnels. It reached the building on the west side and then branches off to each unit. Each unit uses radiant heat to warm the room. The cooled steam is then piped back to the boilers.
The radiators being placed where the cold infiltrates allows that each individual room does not have to have a heating unit. Interior rooms are "heated" by being buffered from the cold.