507335-01
Page 28 of 44
Issue 1624
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 Table 11.
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
These units are 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, reposition the jumper plug marked
HEAT - A, B, C, C (see Figure 32) based on the information
found in Table 11. 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).
Adjust Tap
Airflow amounts may be increased or decreased by 10% by
moving the ADJUST jumper plug (see Figure 32) from the
NORM position to the (+) or (-) position. Changes to the
ADJUST tap will affect both cooling and heating airflows.
The TEST position on the ADJUST tap is not used.
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
Summary of Contents for 80G2UH-V
Page 29: ...507335 01 Page 29 of 44 Issue 1624 ADJUSTING AIRFLOW Table 11 ...
Page 41: ...507335 01 Page 41 of 44 Issue 1624 Wiring Diagram Figure 41 ...
Page 42: ...507335 01 Page 42 of 44 Issue 1624 Typical Field Wiring Diagram Figure 42 ...
Page 43: ...507335 01 Page 43 of 44 Issue 1624 Start Up Performance Check List UNIT SET UP ...
Page 44: ...507335 01 Page 44 of 44 Issue 1624 UNIT OPERATION ...