Maintenance
11
Tronic 3000T – 6 720 892 061 2019/02
element). Upon inspection, the anode rod surface should
appear smooth. If the rod surface appears pitted, bumpy, rusty,
or if the rod is missing completely, then it must be replaced.
To access the anode rod:
▶ Remove the heating element (see Section 5.4 Removing
the heating element).
Original anode rod sizes
•
ES2.5, ES4: length 6½", diameter 5/8"
•
ES8:length 8¼", diameter 5/8"
Certain installations may require more frequent replacement of
the anode rod:
•
recirculation applications;
•
poor water quality;
•
galvanic/electrolytic corrosion
•
high flow applications
In the event of poor water quality, Bosch recommends
consulting a local water treatment professional for water
treatment options. Always ensure the water heater is grounded.
Models ES2.5 and ES4 must be connected only to a properly
grounded outlet. Damage resulting from poor water quality or
failure to replace the anode rod is not covered under the
manufacturer’s warranty. For additional questions, please call
Bosch Technical Service.
5.4
Removing the heating element
▶ Turn off power supply and drain the heater (see previous
section).
▶ Remove the front cover plate, disconnect terminals X, Y and
T.
▶ Unscrew the 4 heating element retaining nuts F.
▶ Remove thermostat temperature sensor from well [B]
located on the element assembly.
▶ Remove the element G.
Fig. 9
Fig. 10
5.5
Descaling the heating element
Scale deposits can affect the heating capability of the element.
Heavy scale can even cause damage to the element. The
element can be descaled either chemically or manually:
▶ Soak the element in white vinegar or other descaling
solution.
▶ Once descaled, rinse well with fresh water, to which you
should add some baking soda,
-or-
▶ Once the element has dried, use a soft brush (non metallic
to prevent damaging the stainless steel sheath) on
element.
▶ Brush the dried mineral off.
6720801072-09.1V
G
Z
F
X
Y
T
A
E
H
B
6720801072-10.1V
G
