Installing A Safety Valve (On-Site); Installing The Dhw Temperature Sensor; Immersion Heater (Accessory, Only For Su200.5 E); Commissioning - Buderus SU120.5 Installations- Und Wartungsanleitung

6

Commissioning

5.2.2

Installing a safety valve (on-site)

▶ Install a type-tested safety valve that is approved for potable water
(DN 20) in the cold water supply ( Fig. 10, page 62).
▶ Observe the safety valve installation instructions.
▶ Terminate the discharge pipe where it will be easily visible in the
frost-protected area above a drain.
– The discharge pipe must be at least equal to the outlet cross-
section of the safety valve.
– The discharge pipe must be able to discharge at least the flow rate
that is feasible at the cold water inlet ( Table 4, page 36).
▶ Attach a notice with the following text to the safety valve: "Never
close the discharge pipe. During heating, water may be discharged
for operational reasons."
If the static system pressure exceeds 80 % of the safety valve response
pressure:
▶ Install a pressure reducer upstream ( Fig. 10, page 62).
Mains pressure Safety valve response
(static pressure) pressure
6 bar
< 4.8 bar
5 bar 6 bar
8 bar
5 bar
8 bar
6 bar
7.8 bar 10 bar
Table 7 Selection of a suitable pressure reducer
5.3

Installing the DHW temperature sensor

Fit one DHW temperature sensor respectively at test port [7] (for the
solar thermal system) and [3] (for the heat source) for capturing and
monitoring the DHW temperature at the DHW cylinder
( Fig. 3, page 60).
▶ Install the DHW temperature sensor ( Fig. 11, page 63). Ensure
that the sensor area has contact with the sensor well surface area
over its full length.
5.4

Immersion heater (accessory, only for SU200.5 E)

▶ Install the immersion heater in accordance with the separate
installation instructions.
▶ When installation of the cylinder is complete, inspect the earth
conductor (including metal connection fittings).
6 Commissioning
NOTICE: Risk of system damage through excessive
pressure!
Excessive pressure can result in tension cracks in the
enamel coating.
▶ Never close the blow-off line of the safety valve.
▶ Commission all assemblies and accessories as specified in the
manufacturer's technical documentation.
6.1

Commissioning the DHW cylinder

Check the DHW cylinder for leaks using potable water
only.
On the DHW side, the test pressure must not exceed 10 bar (150 psi)
positive pressure.
▶ Flush the DHW cylinder and pipework thoroughly prior to
commissioning ( Fig. 13, page 63).
38
Pressure reducer
in the EU outside the EU
Not required
max. 4.8 bar
Not required
max. 5.0 bar Not required
max. 5.0 bar Not required
6.2

Instructing users

WARNING: Risk of scalding at the hot water draw-off
points!
There is a risk of scalding at the hot water draw-off
points if the DHW temperature is set above 60 °C and
during thermal disinfection.
▶ Advise users that they should only draw off mixed
water.
▶ Explain the operation and handling of the heating system and DHW
cylinder, making a particular point of safety-relevant features.
▶ Explain the function and checking of the safety valve.
▶ Hand all enclosed documents over to the user.
▶ User recommendation: Arrange an inspection/maintenance
contract with an approved heating contractor. Have the DHW
cylinder inspected and, if required, serviced annually in accordance
with the service intervals stated ( Table 8, page 39).
▶ Highlight the following for the user:
– Water may be discharged from the safety valve during heat-up.
– The safety valve discharge pipe must always be kept open.
– Service intervals must be observed ( Table 8, page 39).
– Recommendation in the case where there is a risk of frost and
when the user is briefly away: Keep the DHW in operation and
select the lowest possible DHW temperature.
7

Shutting down

▶ If an immersion heater has been fitted (accessory), isolate the DHW
cylinder from the power supply .
▶ Switch off the temperature controller at the control unit.
WARNING: Scalding from hot water!
▶ Let the DHW cylinder cool down sufficiently.
▶ Drain the DHW cylinder ( Fig. 15 and 16, page 64).
▶ Decommission all assemblies and accessories of the heating system
as specified in the manufacturer's technical documentation.
▶ Close the shut-off valves ( Fig. 17, page 64).
▶ Depressurize the indirect coils.
▶ Drain and blow out the indirect coils ( Fig. 18, page 64).
▶ To prevent corrosion, dry out the interior and keep the inspection
aperture covers open.
8

Environmental protection/disposal

Environmental protection is a fundamental principle of the
Bosch Group.
Quality of products, efficiency and environmental protection are equally
important objectives for us. All legislation pertaining to the environment
is strictly observed.
Packaging
We are dedicated in adhering to country-specific disposal standards as
they relate to packaging to ensure optimum recycling. All packaging
materials are environmentally compatible and can be recycled.
Used appliances
Used appliances contain materials that should be recycled.
The assemblies are easy to separate and the types of plastic used are
identified. This allows the various assemblies to be appropriately sorted
for recycling or disposal.
SU120.5 | SU160.5 | SU200.5 | SU200.5 E – 6 720 819 283 (2016/04)