Powershiek County Public Safety Center - Iowa

To improve occupant comfort and after years of struggling with an outdated Niagara/LON control system, ECSI was selected to perform the retrofit.

This 25,000 square foot facility was built in 2008 at a cost of more than 6.3 million dollars and houses the county Sheriffs department, 911/dispatch, 49 bed jail as well as several other county offices.


The Challenge

The unique building HVAC system design required an “outside the box” control strategy to improve the overall operation. The system consists of a geothermal heat pump chiller, air handling unit with energy recovery, 22 vav’s with hot water reheat, 3 heat pumps, 17 heat only radiant ceiling panels and 35 heating/cooling radiant ceiling panels. The chiller had suffered numerous compressor failures due to short cycling and improper control. Comfort in the radiant zones was also a constant complaint from the occupants. The moisture detection sensors used on the radiant panels to detect condensation were also a point of failure that would often cause smoke alarm issues when they failed.


The Process

ECSI used the existing installation infrastructure to keep costs down and installed new Automated Logic BACnet controllers and sensors to control the equipment. The condensation detection sensors were eliminated, and zone humidity sensors were added. Automated Logic’s industry leading ZS combination zone sensors allowed us to reuse the existing sensor wire and rough in but add a humidity sensor to the temperature sensor location. WebCTRL calculates the zone level dew point and then uses both the heating and cooling valves to prevent condensation while also maintaining the zone setpoints.


The Result

The Automated Logic WebCTRL frontend allows the facility staff to monitor and control their building HVAC system with a new level of confidence. Our staff with years of expertise and experience came up with an ‘outside the box’ solution that not only improved the comfort of the occupants, it eliminated a component prone to nuisance failures as well as evening out the load on the chiller.