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Eubank 7AA1024H-1060H & 7AA2024H-2060H I&O Manual 03/2021 Rev.1
Figure 9 - Damper Air Path
b. "A" is the quantity of outside air expressed as a percentage of "C". For example, if the supply air
is 1,220 CFM and 300 CFM of outside air is required, "A" is 25% (300 CFM/1,220 CFM).
Measure the temperature of the outside air.
Multiply the temperature by "A".
c. "B" is the quantity of return air expressed as a percentage of "C". "A" and "B" must equal 100%.
Measure the temperature of the indoor return air.
Multiply the temperature of the indoor air by "B".
d. Calculate what the Tmix should be with the desired quantity of outside air.
Measure the actual temperature of Tmix at the inlet to the supply air blower or at the inlet of the
supply air blower.
Adjust the damper blade until the measured value of the Tmix equals the calculated or desired value
of Tmix.
The motorized damper, Configuration B, can be controlled by an optional relay that allows additional
external control with a choice of 24, 120 or 240V coils to regulate fresh air ventilation in response to
a control located remote from the heat pump unit.
GreenWheel
®
ERV (Configuration H). Setting the correct air flow for the GreenWheel ERV requires
a balometer and a screwdriver.
a. Using best industry standards and practices, measure the fresh air that is being brought into the classroom.
For units with one speed controller (std.), adjust the speed of the intake and exhaust blowers by inserting
a slotted screw driver into the opening on the controller. The speed controller is located on the lower
right side of the GreenWheel ERV assembly. Access to the speed controller is through the return air
grille. Measure the intake air again and adjust the speed of the blowers. Repeat as necessary to meet
the fresh air requirements.