A.O. Smith Water Heater 520 Direct Vent Indoor Service Manual page 57

< For multiple units in an Easy-Link system >
1. Press and hold the "HOT" and "COLD" buttons simultaneously for at least 5 seconds to enter
"Diagnostics Mode".
2. "0" will be displayed on the 9007603005. (See Fig. 1)
3. Scroll to the desired 520 Indoor or 520 Outdoor unit # in the easy-link system by pressing the "HOT" or
the "COLD" buttons to scroll up or down. (Fig. 2 shows that unit #2 is being selecting)
NOTE: The definition of the unit #'s:
"0" will yield information about the Easy-link system as a whole, and numbers "1",
"2", "3", & "4" will yield information about each of the individual 520 Indoor or
520 Outdoor installed in the Easy-link system.
In an Easy-link system of the 520 Indoors or 520 Outdoors, a maximum of four
units of the 520 Indoor or 520 Outdoor's can be linked together.
4. Press the "INFO" button to select the desired unit #.
5. When the desired unit # is selected and fixed, scroll up or down to the needed information (mode #)
of the unit by pressing the "HOT" or "COLD" buttons.
(Fig.3 shows mode #6 is being selected.) When selecting information, please refer to the table on
p.58 p.59 and p.60 for the proper mode #.
6. Press the "INFO" button to select the mode #, and information to which the mode # correlates to will
display on the 9007603005. (Fig. 4)
7. When the "ON/OFF" button is pressed or 5 minutes have elapsed without pressing any buttons, the
display will return to normal.
Whole
diagnostic mode
Fig.1
For example, the figures above show how to arrive at the ON/OFF cycles information for Unit #2 in a
Easy-Link System.
520 Indoor / 520 Outdoor Service Manual
Unit #
Fig.2
57
Mode#
Fig.3
CONFIDENTIAL
Ver. 1.00
Information
Fig.4