17
ELECTRICAL WIRING /
TROUBLESHOOTING
Table E: Control Pin-outs
Pin #
Label
Function
1
CD
24 VAC return power.
2
Dem 1
Enable/Disable - Hot 24 VAC -
Incoming power for the Controller.
Bring hot 24 VAC from the heater
transformer.
3
Dem 2
Indirect DHW Override – Hot 24
VAC – Incoming power for the
demand. Open or close contacts
to supply hot 24 VAC for indirect
DHW override.
4
Com
Outdoor Sensor (if used)
5
Out
Outdoor Sensor (if used)
6
Sys/D
System/Demand Sensor - This is
the primary water temperature
sensor.
7
Boil O
Heater Outlet Sensor
8
Boil In
Heater Inlet Sensor
9
COM/-
Common return lead for all of the
sensors. If all 3 are used, connect
the return leads here.
10
+V (in)
Used for modes 6, 7 or 8 for exter-
nal input of 0-10 VDC or 2-10
VDC. Use terminal 9 for common
lead.
11
Not used
12
C
24 VAC return power
Pin #
Label
Function
13
Pmp
Pump Contact – Not to exceed 5
amps. No power output.
14
Pmp
Pump Contact – Not to exceed 5
amps. No power output.
15
Stg 1
Stage 1, Odd-numbered pin on the
stage connection plug
16
Stg 1
Stage 1, Even-numbered pin on
the stage connection plug
17
Stg 2
Stage 2, Odd-numbered pin on the
stage connection plug
18
Stg 2
Stage 2, Even-numbered pin on
the stage connection plug
19
Stg 3
Stage 3, Odd-numbered pin on the
stage connection plug
20
Stg 3
Stage 3, Even-numbered pin on
the stage connection plug
21
Stg 4
Stage 4, Odd-numbered pin on the
stage connection plug
22
Stg 4
Stage 4, Even-numbered pin on
the stage connection plug
23
Alarm
Alarm notification circuit - may
draw up to 72 VA
24
R
Hot 24 VAC - Incoming power to
the Controller
11
10
9
8
7
6
5
4
3
2
1
12
+V(in)
Com/-
Boil in
Boil O
Sys/D
Out
Com
Dem 2
Dem 1
CD
C
23
22
21
20
19
18
17
16
15
14
13
24
Alarm
Stg 4
Stg 4
Stg 3
Stg 3
Stg 2
Stg 2
Stg 1
Stg 1
Pmp
Pmp
R
A
OFF
B
OFF
Fig. 23: Electrical Connections
