34 | Installation instructions
▶ Check water level in the condensate trap.
Fig. 42 Water level in condensate trap
▶ After filling reassemble all parts in reverse order.
Domestic hot water recirculation
Although recirculation directly through the tankless water heater is
allowed, temperature stability is improved by recirculating through a
mini-tank as shown in fig. 43. By using the design in fig. 43, there is no
recirculation of hot water through the tankless water heater and
therefore, does not affect the heat exchanger warranty. Direct
recirculation through the tankless water heater is permissible, however,
the heat exchanger warranty is reduced; contact Bosch
Thermotechnology for further installation requirements. The following
drawing is provided to outline one possible recirculation design using
the water heater in conjunction with a Bosch electric mini tank water
heater. This schematic is for illustration only and must not be used for
actual Installation without appropriate engineering and technical advice
from a properly licensed professional in the locality where the
installation is made.
Fig. 43 Recirculation application
Full port isolation valve
Circulator pump on timer
Bosch electric minitank
The use of a small electric mini-tank after heater (4-6 gallon size) should
be used for this application and designed so the pump will circulate the
water through the mini-tank and the building's hot water return loop
only. Timed or thermostatically controlled operation of the pump is
commonly done. Contact Bosch Thermotechnology if further
information is needed.
6 720 805 440 (2014/11)