Closed water heater
• Only connect the appliance to a correctly earthed electrical socket. Do not use extension
• Only a prototype-tested diaphragm safety valve may be installed.
• During the heating process, expansion water must drip out of the safety valve outlet.
The outlet pipe of the safety valve must remain open to the atmosphere.
• The safety valve prevents excessive pressure from developing in the water heater during the
heating process. Expansion water must be able to drain off via the safety valve.
• Do not block the outlet pipe!
• The size of the outlet pipe must suit the fully opened safety valve. The blow-off opening of the
safety valve must remain open to the atmosphere.
• The blow-off pipe of the safety group must be installed with a constant decline in a frost-free
room. Regular maintenance and operation of the safety valve are required to remove deposits
and to ensure that the safety valve is not blocked.
• The installation instructions of the safety group must be followed.
• A shutoff valve must not be installed between the safety valve and the water heater.
• Supplied stickers:"For reasons of safety, water must come out of the outlet pipe during the
heating period! Do not block!"– attach the stickers to the outlet pipe in a clearly visible
• The safety valve must be operated regularly to verify its function and to decalcify the valve.
Open outlet water heater
• The water heater is only suitable for use with an open (unpressurised) and a single tap
connection. The warm water outlet is used for pressure compensation and may only be
connected to suitable fittings (Order-No. BZ11114, BZ12411).
• The tap outlet must always remain free. Do not use perlators (diffusers) or shower taps.
• The instructions for unpressurised (open) water heaters that are used with a spray head must
state that the spray head must be regularly cleaned and water scale removed.
• The installation instructions for unpressurised (open) water heaters must state that the water
outlet must only be connected to the specified valves and fittings and NOT to any others.
For technicians only
Mount the hot water wall storage unit as described in the diagram. Observe the instructions in the text. You will find
the diagrams at the beginning of the manual.
Mount close to the tap from which the most hot water will be extracted. A design proofed safety valve combination is to be
installed. In addition, if water pressure exceeds 0.48 Mpa (4.8 bar), a pressure reducing valve is to be installed and adjusted
accordingly. No shut-off valves may be installed between the safety modules and the reservoir. Discharge from the safety valve
must always be open. The safety valve combination for closed operation must be accredited (design proofed):
Safety valve combination AK030300, i.e. safety valve combinations with pressure reducing valve AK040300 can be mounted
with a customary thermostat pre-mixer.
Note: According to the Energy Conservation Act, the temperature in the mains system must be limited to 60ºC for hot water
pipes longer than 5m.
An appropriate overflow mix regulator is to be installed: