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ECONOMIZER
POWER:
1- Terminal strip TB1 energizes the economizer components with 24VAC.
OPERATION:
2- Enthalpy sensor A7 and A62 (if differential enthalpy is used) communicates to the economizer control module A6
when to power the damper motor B7.
3- Economizer control module A6 supplies B7 with 0 - 10 VDC to control the positioning of economizer.
4- The EXH (power exhaust set point) found on the face of A6, is factory set at approximate 50% of the dial range. Econ
omizer control module A6 receives a demand and opens outside dampers 50%. Power exhaust fan relay K65 is ener
gized 30 seconds after dampers are 50% open. K65-1 and K65-2 close, energizing power exhaust fan B10.
5- The damper actuator provides 2 to 10 VDC position feedback.
1
4
2
4
SEQUENCE OF OPERATION
