Install Instructions

Residenal Electric Water Heater Use and Care Guide • 17
INSTALLATION
INSTALLATION

IMPORTANT: The Grid Communica-
on Adaptor must be removed before
aempng to access the thermostat.
NOTE: for the Electronic Thermostat
(ET) changes to remain in eect the Grid
Communicaon Adaptor must not be
reconnected, also read the “Risks During
Operaon” under the “Important Safety
Informaon” secon. If the instrucons
are not clear, contact a qualied service
technician.

The Grid Communicaon Adaptor is in-
tended to serve as the primary interface
for operang the water heater; however,
the Electronic Thermostat (ET) may
control the water heater in the absence
of the Grid Communicaon Adaptor.
The Electronic Thermostat consists of
an electronics box that contains a low
voltage power supply, the thermostat
set point knob, relays to switch between
the upper and lower heang elements,
one control thermistor, a connector for
the lower element control thermistor,
microelectronics to convert the thermis-
tor signals and perform switching and
other logic funcons, and a connector to
e the Electronic Thermostat (ET) to the
Grid Communicaon Adaptor located on
the top of the water heater. The majority
of the self-diagnoscs are located in the
Electronic Thermostat (ET), including the
dry-re protecon intelligence. The ther-
mostat circuit is designed so that when
the upper heang element calls for heat,
the power is directed to that element
even if the lower element is also calling
for heat.

The Green/Red LED light indicates the
status of the electronic thermostat (See
Figure 8).
• Green LED will signal normal opera-
on. The green LED will blink 2 mes
per second to indicate that power is ap-
plied to the upper heang element and
at a faster rate (4 mes per second) to
indicate that the lower heang element
is powered.
• Red LED will ash error codes. If
a fault is detected by the electronic
thermostat, the LED light indicator will
use the red LED to indicate the fault
detected. The ash code sequence is to
consist of 1/2 second ashes of the red
LED each separated by a 1/2 second o
period.
The number of ashes indicates the
fault code number.
(See diagnosc code chart secon in
this manual).
Aer the last 1/2 second “on” period,
the LED will remain o unl a total of 5
seconds has elapsed for the fault indica-
on cycle (there is a 5 seconds delay
before the fault ash paern repeats).
Aer the 5 seconds are completed, the
fault indicaon cycle is repeated starng
with the rst 1/2 second-ash. The ash
sequence will be repeated as long as
the fault remains. Only one fault can
be declared at a me. NOTE: the green
LED is turned o when a fault code is
being displayed, even though the heater
may be operang in limp mode with an
element on. See diagnosc code chart
secon in this manual.
Adjust the thermostat to the desired
temperature seng using the “Setpoint
Knob”. NOTE: If the system diagnosc
yields any codes, reference the Diagnos-
c Code secon in this manual.
Figure 8
Electronic Thermostat (ET)
Diagnostic
LED Light
ECO Reset
Button
Setpoint
Knob
Remove Only After Power Is
Turned O When Replacing Element.
Plastic Guard
Upper
Element












Figure 9
Electronic
Thermostat (ET)
Setpoint
Knob
Thermistor
Wire Harness
Access Door