Installation Instructions

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Table Of Contents

Single Fan VAV AHU

DX Cooling with Options

Application Data Sheet

Figure 1. Single Fan DX VAV AHU with selectable hot water or electric heat and options

Features

• LONMARK compliant with Discharge Air Controller Functional Profile (8505)

• Economizer cycle driven by local dry bulb logic or network override

• Minimum ventilation setting responds to air quality input for demand controlled ventilation

• Multiple options for supply air temperature reset to optimize system performance

• Interoperates with LonMark zone controllers to coordinate occupancy and air conditioning

functions

• Adaptive control of outdoor air dampers responds quickly and stably in any season

• PID control minimizes offset and maintains tighter set point control

• Conforms to the LONMARK interoperability guidelines, enabling information sharing with LONMARK

products from other vendors.

Document No. 588-150 March 2003

Summary of content (11 pages)

PAGE 1
Single Fan VAV AHU DX Cooling with Options Application Data Sheet Figure 1.
PAGE 2
Sequence of Operation Occupied Control General The supply fan starts slowly and runs throughout the occupied mode. A PID control loop continually adjusts the fan capacity to maintain the duct static pressure at setpoint as loads vary in the zones. The duct pressure setpoint may be an adjustable constant, or may be varied automatically by another node to minimize energy consumption.
PAGE 3
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.
PAGE 4
Special Features System Level Occupancy Control Occupancy for an air handler should be coordinated with occupancy for its respective zones. A site may employ more than one of the following interoperation mechanisms to accomplish system level coordination: • The Predator Air Handler Controller may drive occupancy of the zones through bound network variables. • The zone controllers may drive occupancy of the air handler so that it runs to meet their needs.
PAGE 5
In cold climates, to prevent mechanical equipment freeze up, there is a need to keep the air handler warm even when the fan is off. The Predator can cycle or modulate an optional hot water valve to keep the mixed air temperature (or discharge temperature) within a desired range while the fan is off. The Predator can initiate a warm-up sequence for the zones.
PAGE 6
Hardware Map – VAV AHU Termination Set StatTemp StatSetpt StatOvrd In1 In2 In3 In4 In5 In6 OutA1 OutA2 OutA3 OutD1 OutD2 OutD3 OutD4 OutD5 OutD6 OutD7 OutD8 Parameter Set in Element Name I/O Type Factory I/O Setting inputs TEMP SPACE_TEMP IN_UNUSED STAT_SWITCH_DI DISCH_TEMP RETRN_TEMP DUCT_PRESS FAN_STATUS_DI LOW_TEMP_DI HI_PRESS_DI SUP_FAN_CAP_AO OA_DMPR_AO HEAT_COIL_AO SUP_FAN_DO OA_DAMPER_2POS_DO DX_STAGE1_DO DX_STAGE2_DO DX_STAGE3_DO DX_STAGE4_DO HEAT_STAGE1_DO HEAT_STAGE2_DO outputs statTemp st
PAGE 7
Wiring Diagram Note: Route wiring from either the bottom opening when using a J-box or from the base sides as shown in the picture when flat or din rail mounting. The image above is for illustrative purposes only Wiring Recommendations: IN and AO: 20 to 22 AWG DO: 18 to 22 AWG Power: 16 to 18 AWG LON Network: 22 AWG Level 4 Transformer Requirements: Type: Class 2, 24 VAC, 50/60Hz Figure 3. Predator Wiring Diagrams Document No.
PAGE 8
Bill of Materials E A D C B A. Description Product # Predator VAV AHU Controller 6IN 8DO 3AO 587-291 Predator Full Point Wiring Base 587-175 Predator Room Sensors: Sensing Only 587-180 Override 587-181 Temperature Display 587-183(1) Override and Temperature Display 587-185(1) Notes: (1) Sensor will display Fahrenheit or Celsius temperature B. Duct Sensor (100K thermistor) C.
PAGE 9
Configuration Tables The application configuration tables below are typical for a VAV AHU controller. Application Component Variable Name Small VAV Air Handler Core Cooling Coil CW hVACSeqDelay startDelay testTime clgCoilMtr coolCoilCtl coolCoilEn coolDeadBand coolLockout Discharge Air Temp Sensing Duct Pressure Sensing DX Cooling Fan Control Document No.
PAGE 10
Application Component Variable Name Element Factory Setting Modulating Heat Pb Ti Td 68°F (20°C) 300 seconds 0 seconds False 125.0 seconds FALSE 0.90°F (0.50°C) 68°F (20°C) 71.6°F (22°C) Off Enabled 1.8°F (1°C) SRC_RETURN_TEMP 68°F (20°C) 35.
PAGE 11
Control Mode Interaction Table Device Off Fan OA damper DX Stage heat Heat valve off close off off off Fan Only mod close off off off Starting (Fan Proof) mod close off off select Mode Occupied cool heat mod mod stage stage mod mod min off stage mod cool mod mod mod stage mod Unoccupied Idle heat off close off off select mod close off stage mod Safety low other temp safety off off close close off off off off open off Color Key: Red = OFF (not used); Green = Active (fixed in application); Yellow =