Desert Aire SelectAire Plus SP Series, Installation And Operation Manual

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Desert Aire - SP Manual
poolrooms. A building envelope that allows significant infiltration may not be able to
achieve set point. Positive pressures in a pool space will potentially cause
condensation in the wall cavity, mold growth, and property damage. Should the
zone not reach pressure setpoint, it is highly recommended that the maximum CFM in
the MAX EXH. FLOW RATE screen be increased for that mode of operation.
6. Review the actual zone static pressure through the use of independent measurement
device such as a manometer or magnehelic. This can usually be done by slipping the
manometer tubing through a door or window leading outside.
7. If desired, measure the exhaust air flow rates through the use of direct measurement
devices such as hood, velgrid, or anemometer.
8. Repeat the procedure for the other modes as desired by changing the Exhaust Mode.
The modes available are dependent on the types requested at the time of unit order.
These may include “Unocc”, “Occ”, “Event”, “Max. OA”, and “Purge”. Note that controller
power will need to be removed after completing “Purge” mode as the post-purge
operation will lock out outdoor air operation for 30 minutes after purge.
It should be noted that filter changes are important to ensuring that exhaust air and outdoor air are
able to be maintained at the proper flow rates. The SelectAire Plus™ system operation will
automatically adjust to accommodate normal increase in static pressure drop, but excessive filter
loading will restrict airflow. Filters should be monitored and replaced as required.
Evaporator Settings and Cool Exhaust Airflow
There may be additional display screens for the evaporator and cool exhaust airflow. The values are
present from the factory and optimized. No adjustment is required unless instructed by the Desert
Aire Service.
3.2.2 Final Air Balancing
Once the supply air and exhaust air setup have occurred, the unit will automatically adjust the
damper positions and drive speed in each mode of operation.
The outdoor air damper will open and modulate to achieve the pre-deteremined pressure drop set
point of the outdoor air stream pressure plate. This has been determined by the customer requested
occupied mode flow rate and tested at the factory. The exhaust will be controlled by space
pressurization and maintains the negative static pressure set point.
At this point there is a good opportunity to ensure that the commands for operational modes are
being properly sent to the equipment. Command each mode of operation through the method that will
be used on site. Depending on the mode and installation specific, this may occur through the internal
time schedule, a contact closure, or the Building Management System.