Discharge Air Control Cooling (Dacc) Total Reset Limit; Heating - Lennox PRODIGY2.0 Application Manual

To use example values, set the following parameters:
•
Parameter 205 – Set to 70.0°F
•
Parameter 206 – Set to 10.0°F
•
Parameter 204 – Set to 10.0°F (this setting enables Discharge Air Control Cooling return air reset).
14.1.3.

Discharge Air Control Cooling (DACC) Total Reset Limit

Parameter 207 with a default setting of 10.0°F defines the total Discharge Air Control Cooling set point reset limit. This
total limit is the sum of both return and outdoor Discharge Air Control Cooling resets. This parameter limits total
DACC_SP adjustment band and overrides the adjustment bands for parameter 201 and parameter 204 if necessary.

14.2. Heating

The discharge air control heating option automatically cycles up to four-stages of heating to maintain a discharge air
control heating set point.
•
Discharge Air Control Heating option applies to gas/electric and electric /electric units only.
•
Refer to figure 16 for Discharge Air Control Heating heating stages.
•
Adjust parameter 112 to 1 to enable discharge air control.
Discharge air sensor RT6 must be moved to the supply air duct, preferably after a 90 degree branch off of the main
duct.
Discharge Air Control Heating is initiated by an input in one of three ways:
1. W1 input from an external device if M3 unit controller is configured for wired thermostat mode.
Go to SETTINGS > CONTROL > CONTROL TYPE = WIRED THERMOSTAT.
2. Heating demand while in zone sensor mode.
3. Heating demand while in L-Connection room sensor mode.
NOTE: Additional parameters can be set depending on selection choices.
H1=Heating Stage 1
H2=Heating Stage 2
H3=Heating Stage 3
H4=Heating Stage 4
Parameter 174 default is 110.0°F
Parameter 175 DACH UNOCC SETPOINT is adjusted
Parameter 177 DACH FAH STG UP TMR 3 minutes
Parameter 178 DACH FAH STG DN TMR 2 minutes
Minimum Off and Run Times Apply
Figure 16. Discharge Air Control Heating Stages - Default Values Shown
IMPORTANT
110°F + 5°F
Parameter 174 +
115
Parameter 176
OFF
114
113
112
111 H1
ON
110
109
108
110°F - 2°F Diff
Parameter 174 -179
107
106
105
104
62
5°F Discharge Air Control
Heating Dead-band
(All Stages Same Setting)
Parameter 176
OFF
OFF
H2
ON
H3
ON
110°F - (2°F Diff X 2)
Parameter 174 - (Para­
meter 179 X 2)
110°F - (2°F Diff X 3)
Parameter 174 - ( Parameter 179 X 3)
OFF
H4
ON