Lennox Allied Air L83BF, Руководство по установке

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506794-01 Page 14 of 16 Issue 1243
The system must not be in either the passive or active
dehumidification mode when charging a cooling system.
IMPORTANT
Single Stage Cooling
See Figure 14. A call for cooling from the thermostat closes
the R to Y circuit on the blower interface board. The control
waits for a 1-second delay before energizing the circulating
blower to 82% of the selected cooling CFM (passive
dehumidification mode). After 7.5 minutes, the circulating
blower automatically ramps up to 100% of the selected
cooling airflow. When the call for cooling is satisfied, the
circulating blower ramps back down to 82% of the selected
cooling airflow for 1 minute, then shuts off.
7.5 minutes
Y
y
82%
100%
82%
1
min
CALL OFF
Y - Cool Demand Present
- Cool Demand Satisfied
y
Figure 14. Single Stage Cooling
Two Stage Cooling
See Figure 15. A call for 1st stage cooling from the
thermostat closes the R to Y1 circuit on the blower
interface board. The control waits for a 1-second delay
before energizing the circulating blower. The blower motor
runs at 57% of the selected air flow for the first 7.5 minutes
of the 1st stage cooling demand (passive dehumidification
mode). After 7.5 minutes, the blower motor runs at 70% of
the selected cooling air flow until 1st stage cooling demand
is satisfied.
A call for 2nd stage cooling from the thermostat closes the
R to Y2 circuit on the blower interface board. The blower
motor ramps up to 100% of the selected cooling air flow.
When the demand for cooling is met, the blower ramps
down to Y1 until satisfied, then ramps down to 57% for 1
minute, then turns off.
Figure 15. Two Stage Cooling
Y1
y1
57%
100%
CALL OFF
7.5
minutes 70%
Y1 - 1 Stage Cool Demand Present st
- Demand Satisfied 1 Stage Cool st
y1
Y2 - 2 Stage Cool Demand Present nd
- 2 Demand Satisfied nd Stage Cool
y2
1
min
70%
Y1 y2
/
Y1
/
Y2 y1
57%
1
min
57%
Heat Pump
For heat pump operation, clip the jumper wire between R
and O. In heat pump mode, a call for heat pump operation
follows the same sequence as a call for cooling with the
exception that there is a 30-second blower ramp up to
blower CFM.
Continuous Fan
See Figure 16. When the thermostat is set for continuous
fan operation and there is no demand for heating or cooling,
a call for fan closes the R to G circuit and the circulating
blower motor runs at 50% of the selected cooling CFM until
switched off.
Figure 16. Continuous Fan
G
g
50%
CALL OFF
G - Fan Switch ON
- Fan Switch OFF g