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(IE: relay coil) to this circuit. This will damage the CCB and is not

covered under the limited warranty.

connecting an external supervisory control

The enable/disable circuit is accessed from the CCB’s J6 plug

inside the CCB enclosure, see beginning on page 8 to locate the

CCB enclosure. From the factory there is a short (black) jumper

wire installed between pins 8 and 11 of the J6 plug, see Figure

65 on page 67 to locate the J6 plug.
Install field wiring to the enable/disable circuit:
1. Turn off power at the water heater’s on/off switch and the

breaker that supplies power to the water heater.

2. Locate the CCB enclosure.
3. remove the screws from the CCB enclosure cover and

carefully open the CCB enclosure. Note how strain relief for

the wiring is provided between the cover and enclosure along

one edge.

4. Activate the enable/disable circuit; locate the S1 dipswitch on

the CCB, see Figure 65 on page 67.

• Toggle S1 dipswitch #2 to the open position.
• Toggle S1 dipswitch #3 to the open position.

5. Locate the black jumper wire between pin 8 and 11 on the

CCB J6 plug, see Figure 65 on page 67 and Figure 66 on page

68.

6. Cut the black jumper wire in the middle.
7. Strip approximately 1/2 inch of insulation from the two ends

of the black jumper wire.

8. Using wire nuts connect two field supplied control wires to

the two ends of the black jumper wire. Wrap electrical tape

around the wire nut connections.

9. Thread the control wires out of the CCB enclosure with the

other wiring and carefully replace the CCB enclosure cover.

Ensure all wiring is routed through the indented area provided

for strain relief. Ensure no wiring is being pinched.

10. reinstall the CCB enclosure cover screws and tighten.
11. route the control wires inside the junction box on the top

of the water heater, see beginning on page 8 to locate the

junction box. Use an available knock-out to route the wires

inside the junction box.

12. Install field supplied control wiring and conduit as required

by national and local codes between the water heater’s

junction box and the external supervisory control. Connect

the wiring from the external control to the control wires inside

the junction box using wire nuts and electrical tape.

13. Connect the control wiring to a set of dry contacts on the

external control. Follow the control manufacturers instructions

for making connections.

14. restore power to the water heater.

note:

Whenever the external control opens the set of

dry contacts used, heating operation will be disabled.

Whenever the external control closes the set of dry

contacts used, heating operation will be enabled. A

diagonal line and circle appears over the thermometer icon

on the control system’s display when heating operation is

disabled. See the Status Icons descriptions in Table 11 on

page 45.

note:

Ensure the water heater is protected from freezing

temperatures when heating operation is disabled. Damage to

the water heater caused by freezing temperatures is not covered

under the limited warranty.

electrical wiring

All electrical work must be installed in accordance with the

National Electrical Code, ANSI/NFPA 70 or the Canadian

Electrical Code, CSA C22.1 and local requirements.
When installed, the water heater must be electrically grounded

in accordance with local codes or, in the absence of local codes,

with the National Electrical Code, ANSI/NFPA 70 or the Canadian

Electrical Code, CSA C22.1.
If any of the original wire as supplied with the water heater must

be replaced, it must be replaced with 105°C rated wiring or its

equivalent, except in the burner housing. In this case use 200°C

rated wire must be used.

power supply connections

read the requirements for the Power Supply on page 14 before

connecting power.

correct polarity:

The water heater’s control system is polarity sensitive and

will lock out and disable heating operation if the polarity of the

power supply is reversed. The control system will display the

“AC reversed” Fault message on the LCD. The 120 VAC hot

wire from the power supply must connect to the black wire in the

junction box and the 120 VAC neutral wire must connect to the

white wire in the junction box for correct polarity.
Power supply connections must be made as follows:
1. Ensure the power supply is turned off at the breaker or

disconnect switch.

2. remove the junction box cover. See beginning on page 8 for

junction box location.

3. Connect the 120 VAC hot wire from the power supply to the

black wire in the junction box on top of the water heater with a

properly sized wire nut. Wrap electrical tape around the wire

nut and wire end. See wiring diagrams Figure 66 on page 68

and Figure 67 on page 69.

4. Connect the 120 VAC neutral wire from the power supply to

the white wire in the junction box. Wrap electrical tape around

the wire nut and wire end. See wiring diagrams Figure 66 on

page 68 and Figure 67 on page 69.