0
SimpleComfort
®
2811 Electronic Thermostat Conversion to:
Lennox HP21 With CB21 PCB Heat Pump Systems
SC
2811
Electronic Thermostat
24 VAC, return
24 VAC, common
Reversing valve (cooling mode)
Compressor contactor
2nd stage heating circuit
2nd stage cooling circuit
Fan contactor circuit
Note 1:
E terminal on PCB capped
Note 2:
L terminal on PCB capped
R
C
W1
O/B
Y1 W2 Y2
G
W3
R-VR
X
O
Y1
W1
Y2
F
Lennox HP21 with CB21
Low Voltage Terminal Board
Emergency heating circuit
System monitor LED
(capped)
(capped)
E
L
