1. A filter is required for each return−air inlet. Airflow performance includes a 3/4 in. (19 mm) washable filter media such as contained in factory−authorized accessory
filter rack. See accessory list. To determine airflow performance without this filter, assume an additional 0.1 in. w.c. available external static pressure.
2. Blower speed taps are not always in the same order. Factory Default blower connections are as follows:
Heating airflow − BLUE (also used for Continuous Fan)
Cooling airflow − BLACK (enabled when the Y terminal is energized)
ADJUST THE BLOWER SPEED TAPS AS NECESSARY FOR THE PROPER AIR TEMPERATURE RISE FOR EACH INSTALLATION.
3. Airflows over 1800 CFM require bottom return, two−side return, or bottom and side return. A minimum filter size of 20" x 25" (508 x 635 mm) is required.
4. For upflow applications, air entering from one side into both the side of the furnace and a return air base counts as a side and bottom return.
5. Highlighted areas indicate that this airflow range is beyond the range allowed for heating. THESE AIRFLOW RANGES MAY ONLY BE USED FOR COOLING.
6. All airflow that are shown in BOLD exceed 0.58 Watts per CFM at the given external static pressure.
7. The "−" entry indicates an unstable operating conditiong.