Installation & Operation Manual
5
Electrical connections
40
1
2
3
4
5
6
7
8
9
10
+
+
+
+
+
+
+
+
+
+
TANK
SENSOR
B2
B1
A2
A1
2 NO
2 C
1 NO
1 C
INTERMITTENT
LIMITS
CONTINUOUS
LIMITS
HIGH FIRE
ENABLE
LOW FIRE
ENABLE
9
8
7
6
4
3
2
1
10
5
1
2
3
4
5
6
7
8
9
10
+
+
+
+
+
+
+
+
+
+
TANK
SENSOR
B2
B1
A2
A1
2 NO
2 C
1 NO
1 C
INTERMITTENT
LIMITS
CONTINUOUS
LIMITS
HIGH FIRE
ENABLE
LOW FIRE
ENABLE
9
8
7
6
4
3
2
1
10
5
Remote
on/off
Stage 1
1
2
3
4
5
6
7
8
9
10
+
+
+
+
+
+
+
+
+
+
TANK
SENSOR
B2
B1
A2
A1
2 NO
2 C
1 NO
1 C
INTERMITTENT
LIMITS
CONTINUOUS
LIMITS
HIGH FIRE
ENABLE
LOW FIRE
ENABLE
9
8
7
6
4
3
2
1
10
5
Stage 2
Continuous
Alarms
1
2
3
4
5
6
7
8
9
10
+
+
+
+
+
+
+
+
+
+
TANK
SENSOR
B2
B1
A2
A1
2 NO
2 C
1 NO
1 C
INTERMITTENT
LIMITS
CONTINUOUS
LIMITS
HIGH FIRE
ENABLE
LOW FIRE
ENABLE
9
8
7
6
4
3
2
1
10
5
Intermittent
Alarms
Figure 5-4_Stand-alone operation
Figure 5-7_Field installation safety devices
Figure 5-6_Two-stage (high/low fire) water heater
Figure 5-5_Remote on/off water heater
FIELD SUPPLIED
WIRING
1
2
3
4
5
6
7
8
9
10
+
+
+
+
+
+
+
+
+
+
CONNECTION BOARD
TANK
SENSOR
B2
B1
A2
A1
2 NO
2 C
1 NO
1 C
INTERMITTENT
LIMITS
CONTINUOUS
LIMITS
HIGH FIRE
ENABLE
LOW FIRE
ENABLE
9
8
7
6
4
3
2
1
10
5
TANK
SENSOR
REQUIRED IN ORDER
FOR PUMP DELAY TO
FUNCTION PROPERLY
Figure 5-8_Remote sensor for pump delay
Remote mounting of a sensor
To mount remote sensor, follow the guidelines below. Take
care to correctly wire sensors to the unit. Erratic temperature
readings can be caused by poor wiring practices. Twist the
wires between the unit and the remote sensor. Turn wires
at least three or four turns per linear foot of wiring. This
provides common mode rejection of some types of electrical
interferences.
1. Do not route temperature sensor wiring with building
power
wiring.
2. Do not locate temperature sensor wiring next to control
contactors.
3. Do not locate temperature sensor wiring near electric
motors.
4. Do not locate temperature sensor wiring near welding
equipment.
5. Make sure good mechanical connections are made to the
sensor, any interconnecting wiring and the controller.
6.
Do not mount sensor with leadwire end pointing up in an
area where condensation can occur.
7. Use shielded wiring to connect the sensor to the control
when the possibility of an electrically noisy environment
exists. Shielded cable is recommended on all cable runs
of more than 25 feet in length.
NOTICE
Ground the cable shield at the
connection to the water heater
temperature control only. Do not
ground the shielded cable at the sensor
end.
To maintain temperature accuracy,
sensor wires should be at least 18 AWG,
see Table 5B.
TABLE 5B
Remote Wire Connection
Wire Gauge
Max. Allowable Length
12 GA
100 FT
14 GA
75 FT
16 GA
50 FT
18 GA
30 FT
