Overview of Building Temperature Control Parameters
To help the Brown Community understand the operation of the heating and cooling systems on campus, a summary of representative types of building heating and cooling systems, as well as their various control system types, are presented below.
Older campus buildings utilize steam for heating via radiators. Although effective and simple to operate, steam systems are difficult to zone and control to maintain comfortable space temperatures throughout all areas of the building. Many steam systems are zoned such that only one thermostat will control a single floor or an entire section of a building; some buildings have only one to two thermostats for the entire building. In these buildings, areas where the thermostat is located will tend to be comfortable while other areas of the building may become too hot or too cold.
Other campus buildings are heated with hot water via radiators or fancoil units, which incorporate a fan to push conditioned air (heated or cooled depending upon the season) out of the unit. Based on the building size and its configuration, many radiator systems within buildings are zoned such that there is one thermostat for a group of offices, one for each side of a building, or one for each floor of the building. Fancoil systems are generally zoned such that each room or each fancoil unit has its own thermostat, which provides for good comfort levels throughout individual spaces of the building.
Other buildings, such as the larger research, academic and classroom buildings incorporate central forced-air systems for both heating and cooling. Depending on the use and function of the building, these systems may be designed such that there is only one thermostat for a section or floor of a building, or there may be a thermostat for each individual office or space. The latter provides for good individual comfort levels throughout all spaces of a building.
Older, smaller campus buildings and dormitories have no air conditioning or have limited cooling that is provided by individual window-type air conditioners, which have manual temperature controls. Renovated buildings and many of the newer campus buildings typically have central air conditioning that is provided from either local fancoil units located within individual room spaces or from central forced-air type systems - both types typically perform both heating and cooling. Depending on the use and function of the building, these systems may be designed such that there is only one thermostat for a section or floor of a building or there may be a thermostat for each individual office or space.
Dual Temperature Systems:
There are campus buildings that utilize fancoil units or central forced-air systems for heating and cooling are of a changeover design. This type of construction allows for the system to provide for either cooling or heating depending upon the season, but not both at the same time. This design differs from a year-round design, which allows the system to provide both cooling and heating to various parts of a building either simultaneously or within a very short timeframe to convert from one mode to the other.
For most building occupants, the "changeover" design is an issue primarily during the spring and fall "shoulder" seasons where Facilities Management staff must manually change over the operation of the building system from heating to cooling and vice versa. As the changeover process is time-consuming, the changeover schedule is based on the building needs, outside air temperatures, and anticipated weather forecasts. For some buildings there is an additional seasonal concern as parts of the building, such as the perimeter areas, may require heating in the fall while the interior portions of the building may still require cooling.
Temperatures and temperature setpoints within the newer and recently-renovated campus buildings are typically monitored and controlled by state-of-the art, computer-based building control systems. Depending upon the building and location, most of these systems allow the user to manually adjust the room or building zone temperatures individually; where these systems do not allow user control, they are remotely controlled and monitored via the use of room temperature sensors. All of these computer-based building control systems are in turn monitored and supervised by central computer systems.
Other campus buildings do not use central computer-based controls for temperature control. Instead, these buildings have various types of manual or local building control systems installed. These types of building control systems are typically "stand alone" in that they are not remotely monitored by the Facilities Management central computer systems.
Manual building controls are typically items such as the thermostat and fan speed control switches located on fancoil units or air conditioners within individual rooms. Local controls are typically manual thermostats or temperature sensors located in the corridor of a building (for zone control) that are in turn connected to the building local control system. Depending upon the building and location, many of these local control systems allow the user to manually adjust the room or building zone temperatures individually; other locations may contain a sensor only, which does not allow the user to adjust the temperature settings.
For buildings with central computer-based control systems, Facilities Management will set the temperature settings and monitor the temperatures to achieve the University's temperature policy. To view Brown's Temperature Policy, please click on this link: Temperature Policy. For buildings with local control systems, Facilities Management personnel or the occupants will adjust the temperature settings in the building. As theses type of control systems do not report to Facilities Management directly for monitoring and control, it is difficult for us to proactively make the necessary temperature adjustments or respond to "hot/cold" complaints without relying on our customers (students, faculty, and staff) to let us know that their room/building is too hot or too cold.
The building control systems at Brown are categorized into three basic types based on the "controllability" of each system:
- Type 1: User-adjustable thermostats for heating and/or cooling control of individual rooms.
- Type 2: User-adjustable or fixed thermostats for heating and/or cooling control of a group of rooms or entire floors.
- Type 3: User-adjustable or fixed thermostats for heating and/or cooling control of the entire building.