Condensing Heat Exchanger Unit - Bosch Therm C 1210 ES Installation And Operating Instructions Manual

Maintenance and service
▶ Using another line (B), connect the water outlet fitting on
the water heater. Route the other end of this line into a
descaling reservoir.
▶ Using a 3rd line (C) from the descaling reservoir, connect to
the inlet side of circulating pump. Install a filter on the end
of the line in the descaling reservoir.
▶ Make sure all connections are "water tight.".
▶ Fill tank with descaling solution so both lines inside are
submersed. We recommend a straight white vinegar
solution. If using a commercial descalant, refer to
manufacturer's instructions for proper dilution ratio.
▶ Operate the circulating pump.
▶ Make sure there are no leaks and the solution is flowing
from the descaling reservoir through the heater and
returning to the reservoir.
▶ Run solution through the heater until the solution returning
to the descaling reservoir comes out clear. (Changing to a
fresh solution may be necessary during this process).
▶ Disconnect all lines and drain all solution from heat
exchanger. Properly discard of solution.
▶ Position a container below the hot water outlet and connect
cold water supply. Open cold water supply shutoff valve
and flush heat exchanger with clean water.
▶ Shut cold water shutoff valve and reconnect hot water
supply to the water heater.
▶ Reconnect electrical supply to unit, open water shutoff
valves, and return the unit to service.
Fig. 63
[1] Pump
7.4

Condensing heat exchanger unit

The condensing heat exchanger unit must be checked once a
year by a qualified and trained technician. If repairs are needed,
the repairs should be done by a certified Bosch technician.
52
Fig. 64 Condensing heat exchanger unit
Condensing heat exchanger unit maintenance;
▶ Shut off power. Disconnect power cord.
▶ Dismantle all inlet, outlet pipes and the condensate tube
from the condensing heat exchanger unit.
▶ Remove the condensing heat exchanger unit from the
appliance by pulling it towards you.
▶ Dismantle all parts for inspection and cleaning.
Fig. 65 Condensing heat exchanger
▶ Check the condensing heat exchanger for any obstruction.
▶ Flush the condensing heat exchanger unit with water.
▶ Check all gasket and o-rings for damage and replace if
necessary.
C 1210ES/ESC – 6 720 644 887 (2022/04)