Bosch OptiFlow Professional GWH12 1 CTD E23, Installation Manual, Page: 4 / 24

6 720 810 559 (2016/06) OptiFlow Professional
4 | Key to symbols and safety instructions
This appliance must not be installed indoors or in an enclosed
space. This appliance is approved for outdoor installation only.
Do not install this appliance with any modification or alteration.
Failure to install this appliance in accordance with these
installation instructions will void the warranty and may create
an unsafe situation.
Installation
Important information
▶ Determine most suitable location for the appliance. Install
only on an external wall as close as possible to the most
frequently used hot water outlet.
▶ Ensure the mounting structure is capable of supporting the
weight of the appliance once installed. Secure the heater to
the wall using fixings suitable for the weight of the
appliance and the wall material.
▶ Install gas and water isolation valves as close as possible to
the heater. Only use gate valve or full flow ball valve (fixed
mechanism type) for cold water.
▶ Check the cold water supply pressure to ensure it meets
the required supply pressure for the appliance. (see
table 5).
▶ If inlet water pressure exceeds 800 kPa a pressure limiting
valve (500 kPa) MUST be fitted. The preferable location for
the pressure limiting valve is at the water meter.
▶ Where the pressure limiting valve is less than 3 metres from
the hot water unit, it must be fitted in conjunction with a
cold water expansion valve (700 kPa), between the water
heater and the pressure limiting valve.
▶ Failure to comply with this requirement may void the
warranty.
▶ Refer to AS/NZS5601 for the relevant gas pipe sizing.
▶ After finishing the gas piping system, the pipes must be
thoroughly purged and leak tested. This test must be
performed with the gas isolation valve of the appliance
closed.
▶ Ensure the gas pressure and flow through the regulator are
appropriate for the consumption of the heater (see table
5). Refer to As/NZS5601 and AS3500.1 for the relevant
pipe size.
Note: Incorrect pipe sizing or gas supply pressure may cause
the appliance to under perform. Service calls for incorrect pipe
sizing and/or gas pressure, will NOT be covered under
warranty.
Safety of electrical appliances for domestic use and similar
purposes
The following requirements apply in accordance with EN
60335-1 in order to prevent hazards from occurring when
using electrical appliances:
DANGER:
This appliance must not be installed indoors
or in an enclosed space in accordance with
AS/NZS5601.
DANGER: Explosion Risk!
▶ Always turn off the gas valve before
carrying out any work on components
which carry gas.
DANGER: Appliance malfunction!
This appliance must be installed with no
obstructions to air entry openings.
▶ Periodic checking of openings to ensure
no blockage or obstruction of the air
openings from plants, debris or insects
must be carried out.
The installation of gas, water, and electrical
supply, and the initial startup are to be
performed by an authorised person.
Not suitable for pool or spa pool applications.
Not suitable for commercial boosting of
warm water recirculation systems.
Installation in marine environments can lead
to premature corrosion. Premature corrosion
due to the installation environment would not
be covered by warranty.
All gas appliances require adequate air intake
to ensure correct combustion. Insects and
dirt ingress may affect combustion causing
sooting. If you notice sooting from the flue
outlet the unit would require servicing. Pest
and dirt ingress is not covered by the
manufacturers warranty.