Selecting Minimum Low And Minimum High Damper Positions - Lennox Prodigy 2.0 Application Manual

Control Parameter
P Screen Name
105 DEHUMID MODE
106 DEHUMID SETPOINT
107 DEHUMID DEADBAND
Control Parameter
No. Screen Name
166 FAH REHEAT OAT SP
167 FAH REHEAT DAMPER
168 FAH REHEAT SP
6.5.

Selecting Minimum Low and Minimum High Damper Positions

The following tables reference minimum damper positions which have two possible values for units with MSAV blower
option, Parameter 9 = MIN DAMPER LOW BLWR or Parameter 132 = MIN DAMPER POSITION. Which minimum damper
position is used depends on a mid-point calculation and actual blower speed.
The mid-point speed is determined as (Min Cool CFM + Max Cool CFM)/2 from those available for the number of
compressors installed. Then if actual blower speed is < mid-point Parameter 9 is used, otherwise Parameter 132 used.
Table 20. Summary Of Dehumid Parameter Options
Control Value
Short
Description
Min.
Dehumidification
0
Mode
Dehumidification
0.0
Set Point
Dehumidification
Deadband Set 1.0
Point
To control humiditrol dehumidification by a digital output, the
user must enabled the Humiditrol option via the user inter­
face:
SETUP > INSTALL
NOTE: Configuration ID 1, position 1 must be set to H.
Table 21. Outside Air For Dehumidification Parameters
Short Description
Fresh Air Heating Control Reheat
Outdoor Air Temperature Set
Point
Fresh Air Heating Control Reheat
Damper Position
Fresh Air Heat Control Set Point
Default Max.
Unit
0 - No
Humiditrol
is installed
6 - All
7 Option
Others
(Check unit
parameter
label)
Check unit
parameter
label as
default may 100.0 % RH
be altered
at factory
test.
3.0 10.0 % RH
Control Value
Min. Default Max.
20.0 45.0 60.0
5.0 40.0 100.0
40.0 40.0 70.0
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Description
Dehumidification Mode
0- No reheat.
1- Supermarket reheat using De-Humidistat
(wired thermostat mode only)
2- Supermarket reheat using relative humidity
sensor.
3- Humiditrol reheat. Conditions: Blower must
be energized, Must be occupied, At least
one previous cooling demand.
4- Relative Humidity measurement / display.
No Supermarket or Humiditrol reheat.
5- Humiditrol reheat. Conditions: At least one
previous cooling demand.
6- Humiditrol reheat. Conditions: Blower must
be energized, Must be occupied.
7- Humiditrol reheat. Conditions: None
Percent relative humidity where supermarket or
Humiditrol reheat demand is energized. Used with
dehumid mode option 2, 3, 5, 6 or 7.
Dehumidification is de-energized at set point –
dead-band (Parameter 107).
When Parameter 105 dehumidification options
2, 3, 5, 6 or 7 is set, then dehumidification is :
•
ON when relative humidity is equal to or
greater than Parameter 106.
•
OFF when Relative Humidity is less than
Parameter 106 minus Parameter 107.
Unit Description
Outdoor air temperature set point
that enables fresh air heating for
°F reheat demand and opens
damper to Parameter 167 when
outdoor air is less than set point.
Fresh air damper position during
Fresh Air Heating reheat opera­
%
tion.
•
Fresh Air Heating Reheat set
point.
•
When Fresh Air Heat set
°F
point (Parameter 156) is en­
abled and outside air is being
used for dehumidification.