Dhw Heating; Systems For Dhw Heating; Dhw Temperature Control; System Examples - Bosch UT-L 1 Technical Manual

8

DHW heating

8.1

Systems for DHW heating

The UNIMAT UT-L boilers can be used for central DHW
heating. They can be combined with any Bosch DHW
cylinder. The WST cylinders are available as horizontal or
vertical versions in different sizes with up to 6000 l
capacity. Subject to application, they are equipped with
an internal indirect coil or external heat exchanger.
The DHW cylinders can be used singly or in combination
with other cylinders. With the primary store system,
different cylinder sizes and different heat exchanger sets
can be combined. This means system solutions are
available for any demand and many applications.
VS
RS
Fig. 29 DHW heating according to the cylinder principle
with an internal indirect coil
AW Hot water outlet
EK Cold water inlet
RS Cylinder return
VS Cylinder flow
VH
RH
Fig. 30 DHW heating according to the primary store
principle with an external heat exchanger
AW Hot water outlet
EK Cold water inlet
RH Fuel return (to boiler)
VH Fuel flow (from boiler)
UNIMAT
AW
EK
6 720 640 417-11.1il
AW
EK
6 720 640 417-12.1il
8.2

DHW temperature control

The DHW temperature is adjusted and controlled by the
CFB control system for DHW heating. Both versions are
matched to the heating circuit control unit and offer
many application options.
9

System examples

9.1 Information regarding all system
examples
The system examples in this chapter show options for
the hydraulic connection of the UNIMAT UT-L boilers. In
addition, the examples show important control and
electrical connections for the relevant application.
Detailed information regarding the number, controls,
equipment level and design of further heating circuits, as
well as the installation of DHW cylinders and other
consumers, can be found in the relevant technical
guides.
Information regarding further options for system layout
and engineering aids are available from Bosch technical
consultants. Specialists at your local sales office can
create a control panel layout tailored to your needs. In
this way, Bosch offers an entire matching concept right
through to commissioning the heating system.
The diagrams and associated design information for the
system examples with the UNIMAT UT-L boilers offer
non-binding information regarding a possible hydraulic
connection. No claim is made as to their completeness.
Each system example is a non-binding recommendation
for a certain version of the heating system. Practical
implementation is subject to currently applicable
technical rules.
List of abbreviations
Abbr. Meaning
BR / BRII Burner (stage I / stage II)
Direct Digital Control (overriding control
DDC
unit)
Building management control (overriding
GLT
control unit)
FK Boiler water temperature sensor
FR Return temperature sensor
FRS Strategy return temperature sensor
FV Flow temperature sensor
FVS Strategy flow temperature sensor
Additional sensor for the return
FZ
temperature
HK Heating circuit
HB High temperature heating circuit
KR Flow-check valve
LT Low temperature heating circuit
PH Heating pump
PK Boiler circuit pump
PWT Heat exchanger pump
RK Boiler return
Table 26 Summary of frequently used abbreviations
DHW heating | 47
6 720 807 794 (2013/04)