York BP120, BP 090 installation manual Enthalpy Set Point Chart, Indoor Air Quality Aq

Models: BP120 BP 090

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INDOOR AIR QUALITY AQ

66307-YIM-B-0606

For a dual enthalpy operation, carefully turn the set point adjusting screw fully clockwise past the "D" setting.

POWER EXHAUST DAMPER SET POINT (WITH OR WITH- OUT POWER EXHAUST)

With no power exhaust option, adjust the Exhaust Air Adjustment Screw fully clockwise. This will allow 2nd stage cooling to operate.

With power exhaust option, each building pressurization requirement will be different. The point at which the power exhaust comes on is determined by the econo- mizer damper position (Percent Open). The Exhaust Air Adjustment Screw should be set at the Percent Open of the economizer damper at which the power exhaust is needed. It can be set from 0 to 100% damper open.

INDOOR AIR QUALITY AQ

Indoor Air Quality (indoor sensor input): Terminal AQ accepts a +2 to +10 Vdc signal with respect to the (AQ1) terminal.

When the signal is below it's set point, the actuator is allowed to modulate normally in accordance with the enthalpy and mixed air sensor inputs. When the AQ signal exceeds it's set point setting and there is no call for free cooling, the actuator is proportionately modulated from the 2 to 10 Vdc signal, with 2 Vdc corresponding to full closed and 10 Vdc corresponding to full open. When there is no call for free cooling, the damper position is limited by the IAQ Max damper position setting. When the signal exceeds it's set point (Demand Control Ven- tilation Set Point) setting and there is a call for free cooling, the actuator modulates from the minimum position to the full open position based on the highest call from either the mixed air sensor input or the AQ voltage input.

Optional CO2 Space Sensor Kit Part # 2AQ04700324

Optional CO2 Sensor Kit Part # 2AQ04700424 Replace the top rear access panel on the unit.

FIGURE 20 - ENTHALPY SET POINT CHART

Unitary Products Group

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York BP120, BP 090 installation manual Enthalpy Set Point Chart, Indoor Air Quality Aq