Bosch Tronic 3000T ES 2.5 User Manual Download

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Maintenance

Tronic 3000T – 6 720 801 072 (2018/04)

Turning heater on
For models which are not fitted with a switch:

▶ Supply power to the water heater by plugging in the power

cord (models ES2.5, ES4) or turning on the circuit breaker
(model ES8). If the light does not come on, turn the control
knob in a clockwise direction.
The light will come on until water temperature has reached
the thermostat temperature setting. The light will come
back on any time the water temperature inside the tank
drops below the thermostat setting.

4.2

Temperature setting

The temperature of the hot water is adjusted by rotating the
knob M located on the front cover. Temperature range is 65 -
145 °F.

▶ Turn the knob clockwise to increase temperature.
▶ Turn the knob counter-clockwise to decrease temperature.

Fig. 9

Maintenance

Periodic maintenance

5.1

Removing the cover

▶ Pry off the round cover plate [V] from its right hand edge

[W] with a small flat-head screwdriver.

▶ Remove the Phillips screw revealed beneath the round

cover plate.

▶ The cover [C] can now be removed by pulling out its left-

hand edge. When reassembling, work in the opposite way
being careful to insert the tongue of the cover into the slot.

5.2

Draining the heater

If the heater has been installed with flexible hoses:

▶ Shut off the power supply.
▶ Turn the heater upside down over a sink to drain the water

out of it.

-or-

it can also be emptied by:

▶ Siphon through the inlet side hose.
▶ Keep a hot water faucet open while siphoning.
-or-

If the heater has been installed with rigid piping:

▶ Siphon the water out through any (lower) service valve on

the (inlet side).

▶ Keep a hot water faucet open while siphoning the water

out.

5.3

Inspecting the anode rod

The purpose of the anode rod (



Fig. 12, [N]) is to protect the

tank against corrosion. It is critical that the anode rod be
inspected once a year to determine whether it requires
replacement. To access the anode rod, the heating element
must be removed (see Section 5.4 Removing the heating
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

CAUTION:
Do not attempt to repair this water heater
yourself. Call a service person for
assistance. Always turn off the power supply
to the heater prior to servicing or draining
the heater.

For most of these operations, the water will
have to be drained from the heater. For all of
these operations the cord should be
disconnected (ES2.5 and ES4 only) and the
front cover removed.