Installation Instructions

Unoccupied Heating Mode
The air handler starts in response to a heat or warm-up command from the network or
measured zone temperature below the unoccupied setpoint. The Predator modulates the
supply fan capacity to maintain measured duct pressure at the duct static pressure setpoint.
The hot water coil or staged heat is operated to maintain the supply air temperature at the
heating setpoint. The stages of DX cooling are off and the outdoor air damper is closed.
Safety Shutdown
Low Temperature
If a Low Temperature is detected the OA damper closes and the fan shuts off. The stages of
cooling are turned off. The optional hot water coil valve opens fully; optional staged heat is
turned off. The system may be configured to re-start automatically after the condition clears,
or to remain shut down until a manual reset.
Other Safeties
Any number of other safety devices, such as smoke detectors or a high duct pressure switch,
may be applied to shut the unit down. The Predator turns off the fan, closes the OA dampers,
closes the hot water coil valve and turns off the cooling stages. The Predator indicates an
alarm condition over the network, and remains shut down until reset manually.
Off
In this mode, the heating coil valve and OA damper are closed, and the cooling stages and fan are off.
Temperature Control Sequence Diagrams
100% Open
Damper
Minimum
0%
Heating
Valve
DX
Cooling
Air Conditioning Load
Outdoor Air
Damper
The Predator sequences heating, cooling and outside
air as needed to meet air contidioning load.
Document No. 588-150 Page 3 of 11