Appendix A. Flow Diagrams & Wiring Diagrams - Lennox ComfortSense 7000 Series Programming And Application Manual

Appendix A. Flow Diagrams and Wiring Diagrams
RUN EQUIPMENT IN
NORMAL COOLING
MODE
RUN EQUIPMENT IN
NORMAL HEATING
MODE
DEACTIVATE ALL
EQUIPMENT
Figure 15. ComfortSense
LEGEND
HBSP − High Balance Set Point
LBSP − Low Balance Set Point
ODT − Outdoor Temperature
NOTES
LBSP and HBSP must not be set closer than 2ºF
2nd stage lock in temperature −20ºF to 75ºF (OFF)
Temperature
Heat Pump Heat Only
HBSP
Heat Pump or Gas/Oil Heat
LBSP
Gas/Oil Heat Only
ODT
< LBSP − 3
YES
?
NO
ODT
< LBSP − 3
?
YES
NO
De−energize
Y1 or Y1&Y2,
and G
506230−01 05/09
START
there a cooling
YES
demand
NO
there a heating
YES
demand
NO
there a
dehumidification
NO
demand
YES
EITHER true:
ONE OR
outdoor temp. > 95ºF;
BOTH TRUE indoor temp. < 65ºF
®
Model L7742U Thermostat Operation with Humiditrol
Operation
A
YES YES
NO
NO Upstage
2nd stage
timer expired
demand
?
?
ODT
YES NO
< HBSP − 3 or
(if HBSP is
OFF)
?
YES YES
NO NO Upstage
3rd stage
timer expired
demand
?
?
Figure 16. Dual Fuel Flowchart
HUMIDITROL
Is
?
Is
?
Humiditrol Comfort
Adjust setting is:
Is
?
Is
NEITHER
IS TRUE
?
demand (W1) or EM
YES
De−energize
Y1, Y2, G
Energize Y1, B, Stg1
G and start
NO
upstage timer
YES
Indoor heat
demand
?
NO
YES
Indoor heat
demand
?
Page 22
RUN
Is indoor
MAX YES
temperature > 2ºF
above heating set
point
?
NO
Is
indoor temp.
MID
greater than the heat
YES
setpoint plus the cool
setpoint divided by 2?
NO
Is indoor
YES
temp. > 2ºF below
cooling set point
MIN
?
NO
®
START
NO
Indoor heat
demand
?
YES
Gas/oil
heat (non−HP)
YES
heat demand
?
NO
ODT above
LBSP +3
NO
?
A
YES
Compress-
or speed 1 (Y1
2nd stg
W1
only) ?
HP (Y2) or
Gas (W1)
NO
?
Y2
ODT
> stg2 (Y2)
lock in temp
NO
?
YES
HP
Stg2
Energize Y1, Y2,
stage
B, G and start
demand
upstage timer
?
EDA Enabled
De−energize
W1 and W2
HEAT PUMP
LOCKOUT
Energize 1st
stage gas/oil heat
(W1) and start
upstage timer
Indoor heat
demand
NO
?
YES
Upstage timer
expired
YES
?
NO
4th
stage demand
or 2nd stage gas/oil
NO
demand (W2)
?
YES
Energize W2
YES
NO
Indoor heat
demand
?