Comfort Stat CDT901 User Manual
Page 96
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CDT900 Series Touchscreen Programmable Thermostata
Table 11. Sequence of Operation for Heat Pump Systems.
System Setting
Fan Setting
Call for Action
Energize Terminals
Screen Message
Off Auto
None
O/Ba
None
Cool Auto None O/Ba None
Cool or Auto
Auto
Stage 1 Cooling
Y, G, O/B
a
Cool
On
Cool or Auto
Auto
Stage 1 and Stage 2
Cooling
Y, Y2
d
, G, O/B
a
Cool
On
Heat Auto None O/B
a
None
Heat or Auto
Auto
Stage 1 Heating
Y, G, O/B
a
Heat
On
Heat or Auto
Auto
Stage 1 and Stage 2
Heating
Y, AUX
c
, G, O/B
a
Aux Heat On
Heat or Auto
Auto
Stage 1, 2 and 3
Heating
Y, Y2d, AUX
e
, G,
O/B
a
Aux Heat On
Em. Heat
Auto
None
L
b
, O/B
a
None
Em. Heat
Auto
Stage 1 Heating
E, G, Lb, O/B
a
Heat
On
Em. Heat
Auto
Stage 1 and Stage 2
Heating
E, AUX, G, L
b
, O/B
a
Aux. Heat On
a
Configure O/B in Installer Setup. Based on last piece of equipment called (cooling = O or
heating = B).
b
Red LED is on. See LED Indication section for more details.
c
If Installer Setup System Type is set to 2Heat/1Cool Heat Pump with Auxiliary Heat.
d
If Installer Setup System Type is set to 3Heat/2Cool Heat Pump with Auxiliary Heat.
e
This terminal does not energize if Installer Setup System type is set to 2 Heat/2 Cool Heat
Pump with no Auxiliary Heat
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