Westmar Middle School is a two-story building comprised of 125,649 sq. feet. There are 44 classrooms, a gym, media center, cafeteria and auditorium.
Envirotrols Group's goal was to dramatically reduce electric and gas consumption and to monitor operation of the boilers, while at the same time reaching payback in less than 2 years.
Envirotrols Group's installed system controlled:
- Controlling hot water reset through the
existing pneumatic three-wayvalve
- Three zones using six wireless sensors
tied into the existing pneumatic control
system. The ASI system interfaces with
the existing system to provide occupied/
unoccupied schedules to these three
zones. The pneumatic system controls
the individual classrooms and air handling units.
- Controlling the building in an unoccupied through multiple schedules, space and outdoor temp.
The following are the actions that Envirotrols Group implemented to reach the set goal:
- Provided one ASI Controls panel, equipped with Expert software and a web-based front-end graphical software. All field installation was provided by the school district, Envirotrols Group provided startup, cutover, and commissioning.
- Allegany County Public Schools (ACPS) supplied a static IP address, allowing access to the school over the internet.
- ACPS standards for unoccupied heating and cooling setpoints implemented
- Provided lead/lag control to even out run time on boilers and pumps.
- Provided control on boilers based on building heating loads.
- Developed occupied and unoccupied schedules for the HVAC units; provided push-buttons on wall sensors to give timed overrides to teachers working hours outside of the occupied schedule
- Heaters for all areas were locked out when outside air temperature is above 55 degrees F.
- Staggered start of all HVAC equipment to prevent demand spikes
- Provided freeze protection for pumps by starting pumps when outdoor air is below setpoint
- Implemented use of counters and trends. Counters allow us to look at equipment start and run times. Trends allow ACPS to verify they are maintaining temperature. All this data is used to further refine the operation of the system to make it even more efficient.
Energy Solutions for Schools
"The total energy savings from one heating season total up to $27,320.69 ($20,830.83 gas and $6,489.87 electric). Our total return on investment in the project was five months. I think it's fair to say that ASI systems provide the tools to push the building systems beyond the limits of the old pneumatic/time clock systems."
Jay Marley, P.E.
Supervisor of Maintenance & Construction
Allegany County Public Schools
Toll Free: 800-344-4984