Steffes 7140 - Manual (Page 38)

Appendix
Appendix
n
A.11 Comfort Plus Commercial Hydronic
System Low Voltage Wiring Diagram - Model 7120 with Variable Speed
The "R" and "C" positions in the low voltage terminal
strip may be used as a source of 24 VAC for powering
external low voltage devices (60 VA maximum).
HAZARDOUS VOLTAGE: Risk
of electric shock. Can cause
injury or death. All low voltage
wiring must be segregated
from line voltage circuits in
the system.
WARNING
1
2
"Y2"
"R"
CORE D
COR
E
C
RELAY 8
RELAY 7
RELAY 6
RELAY 5
RELAY 4
RELAY 3
RELAY 2
RELAY 1
20V DC
CORE LIMITS
DISCHARGE
(OPTIONAL
HANDLER)
SENSOR
DISCHARGE
Relay Inputs
O
u td
oor
O
u td
oor Pump VAC
24
2
Water
P3 P2 P1
Air
P11
W/
Y1 AUX Y2
J5 Y1 Y2
RLY1
J2 D1
Blower
B
C
D P4
P5
D2
J4
J3
P6
H/E
Speed
Blower
A
O G
J6 W/E
Y1 C R
J1
P
To Control Board
P7
2 Y2 2 O RP
R
P8
C
P9
NC AP COM NO
Thermostat Peak Heat Aux.
CONTROL BOARD
SENSOR
AIR
AIR
M
3
4 "R"
"O2" ORANGE
WHITE 6
WHITE/RED
RED/BLACK
BROWN
WHITE/BLACK
YELLOW/BLACK
GREEN
BLACK
WHITE
ORANGE
YELLOW
BLUE
BLUE/BLACK
GRAY
WATER
RED
15
20
17
19
18
16
10
13
14
11
12
9
7
8
TO CONTROL BOARD
TRANSFORMER
GROUNDED
BLUE
TO LOW VOLTAGE BOARD
YELLOW
YELLOW
WHITE/BLACK
YELLOW/BLACK
ORANGE/BLACK
ORANGE
R
1
5
3
4
2
C
WHITE/BLACK
YELLOW/BLACK
WHITE/BLACK
ORANGE
BROWN
BLUE/BLACK
BLUE
GRAY
GREEN
BLACK
RED/BLACK
WHITE
YELLOW
RED
WHITE/RED
WHITE
ORANGE
13
12 "O"
15
14
19
20
17
18
16
"DS"
"SC"
"RS"
"OS"
"G"
"AP"
"P"
"C"
5
6
10
8
9
11
7
"RP"
"W"
"Y"
"E"
"NC"
"NO"
"COM"
75 VA
TX2
TRANSFORMER
UN-GROUNDED
BLUE
75 VA
YELLOW
TX1
YELLOW
YELLOW
M A
M P