F.Readjust temperature on the thermostat to engage the second stage of cooling (Y2).
The damper motor should return to previously set minimum position. Compressor motor should start.
G.Switch thermostat to OFF fan and OFF heat/ cool positions to
16.Replace control access panel and mist eliminator.
17.Remove blank off plate or barometric fresh air damper if installed on the service access panel. Plug the four (4) holes used to mount the BOP or BFAD with the plastic plugs supplied with the economizer.
18.Replace service access panel.
19.Economizer is now ready for operation.
ECONOMIZER – WA, WL & WH SERIES
FEATURES
•One piece construction – easy to install with no mechanical linkage adjustment required.
•Exhaust air damper – built in with positive closed position. Provides exhaust air capability to prevent pressurization of tight buildings.
•Actuator motor – 24 volt, power open, spring return with built in torque limiting switch.
•Proportioning type control – for maximum “Free Cooling” economy and comfort with up to 100% outside air.
•Enthalpy control to monitor outdoor temperature and humidity – adjustable.
•Minimum position potentiometer – adjustable to control minimum damper blade position.
•Mixed air sensor to monitor outdoor and return air to automatically modulate damper position.
ECONOMIZER SEQUENCE OF OPERATION
Condition A – Cool Outdoors
First stage cooling closes and powers the economizer dampers to economizer mode and the indoor blower starts. Mixed Air Sensor senses a mixture of return air and outdoor air and modulates the dampers accordingly. Compressor operation is inhibited.
(See Figure 5.)
If second stage closes on the thermostat, the dampers return to the closed or minimum position setting and the compressor starts for mechanical cooling.
FIGURE 5
ECONOMIZER OPERATION
Manual
