Bard SH611 Installation Instructions Manual - page 16
Manual 2100-411G
Page
16 of 23
LOW VOLTAGE CONNECTIONS
These units use a grounded 24 volt AC low voltage
circuit.
The “R” terminal is the hot terminal and the “C”
terminal is grounded.
“G” terminal is the fan input.
“Y” terminal is the compressor input.
“B” terminal is the reversing valve input. The reversing
valve must be energized for heating mode.
“R” terminal is 24 VAC hot.
“C” terminal is 24 VAC grounded.
“L” terminal is compressor lockout output. This
terminal is activated on a high or low pressure trip by
the electronic heat pump control. This is a 24 VAC
output.
“W2” terminal is second stage heat (if equipped).
“O1” terminal is the ventilation input. This terminal
energizes any factory installed ventilation option.
“E” terminal is the emergency heat input. This terminal
energizes the emergency heat relay.
NOTE: For total and proper control using DDC, a
total of 6 controlled outputs are required (5 if
no ventilation system is installed). For proper
system operation under Emergency Heat
conditions where the compressor needs to be
deactivated, the B-W2-E outputs need to be
energized. Removing the Y (compressor) signal
alone turns the compressor off, but does not
activate the additional circuitry embedded in
the heat pump for proper and complete
operation.
LOW VOLTAGE CONNECTIONS
FOR DDC CONTROL
Fan Only
Energize G
Cooling Mode
Energize Y, G
Heat Pump Heating
Energize Y, G, B
2nd Stg Heating
Energize G, W2, Y, B
w/Heat Pump (if employed)
Ventilation
Energize G, O1
Emergency Heat
Energize B, W2, E, G
TABLE 4
WALL THERMOSTAT
t
a
t
s
o
m
r
e
h
T
s
e
r
u
t
a
e
F
t
n
a
n
i
m
o
d
e
r
P
8
5
0
-
3
0
4
8
)
1
5
1
1
D
0
2
2
5
H
T
(
t
a
e
H
e
g
a
t
s
2
;
l
o
o
C
e
g
a
t
s
2
e
l
b
a
m
m
a
r
g
o
r
P
-
n
o
N
c
i
n
o
r
t
c
e
l
E
r
e
v
o
e
g
n
a
h
c
l
a
u
n
a
M
r
o
o
t
u
A
0
6
0
-
3
0
4
8
)
5
4
4
-
0
2
1
1
(
t
a
e
H
e
g
a
t
s
3
;
l
o
o
C
e
g
a
t
s
3
c
i
n
o
r
t
c
e
l
E
e
l
b
a
m
m
a
r
g
o
r
P
-
n
o
N
/
e
l
b
a
m
m
a
r
g
o
r
P
l
a
n
o
i
t
n
e
v
n
o
C
r
o
P
H
r
e
v
o
e
g
n
a
h
c
l
a
u
n
a
M
r
o
o
t
u
A