Allied Air Enterprises A80UH2V - Manual (Page 28)

506471-01 Page 28 of 41 Issue 1034
Active Dehumidification
To achieve additional dehumidification, clip the jumper wire
located below the DEHUM terminal on the integrated ignition/
blower control board and connect a humidity control that
opens on humidity rise to the DEHUM and R terminals. The
DEHUM terminal on the control board must be connected
to the normally closed contact of the humidity control so that
the board senses an open circuit on high humidity. In this
setup, the variable speed motor will operate at a 18%
reduction in the normal cooling airflow rate when there is a
call for dehumidification.
Both the passive and active dehumidification methods
described above can be utilized on the same furnace.
Circulating Airflow Adjustments
Cooling Mode
The units are factory set for the highest airflow for each model.
Adjustments can be made to the cooling airflow by
repositioning the jumper plug marked COOL – A, B, C, D
(see Figure 32) based on the information found in the table.
To determine what CFM the motor is delivering at any time,
count the number of times the amber LED on the control board
flashes. Each flash signifies 100 CFM; count the flashes and
multiply by 100 to determine the actual CFM delivered (for
example: 10 flashes x 100 = 1000 CFM).
Heating Mode
The unit as shipped is factory set to run at the middle of the
heating rise range as shown on the unit rating plate. If higher or
lower rise is desired, change the airflow 15% up or down by
moving the ADJUST jumper plug (see Figure 32) from the NORM
position to the (+) or (–) position. This adjustment will also cause
the cooling airflow to be raised or lowered by 15%.
The TEST position on the ADJUST tap is not used.
The jumper plug on the HEAT tap should remain in the position
(A, B, C, or D) listed in the HEAT Setting column in the table
found in Figure 32. Changing the setpoints may not increase or
decrease heating blower speeds. In some cases, running the
blower with the heat settings in the wrong position may cause
the furnace to operate outside the furnace’s intended temperature
rise range.
Continuous Blower Operation
The comfort level of the living space can be enhanced when
using this feature by allowing continuous circulation of air
between calls for cooling or heating. The circulation of air
occurs at half the full cooling airflow rate.
To engage the continuous blower operation, place the fan
switch on the thermostat into the ON position. A call for fan
from the thermostat closes R to G on the ignition control
board. The control waits for a 1 second thermostat debounce
delay before responding to the call for fan by ramping the
circulating blower up to 50% of the cooling speed. When
the call for continuous fan is satisfied, the control immediately
ramps down the circulating blower.
Figure 32
ADJUST, HEAT, and COOL Taps
on Integrated Ignition/Blower
Control Board