Id.Nr.: 229224-9 •
17
District heating tank FSN and FSN-E
via the funnel or outlet pipe.
b) In the case where safety valves are installed before water heaters, a check should be made as to
whether the safety valve reacts when the water heater is heated up. This can be verified by way
of water egress out of the outlet pipe.
Implementation:
Operator, Installation Company
Interval:
every 6 months
Servicing and repair:
If no water escapes when the water heater is heated up or if the safety valve is permanently leaky,
then an attempt should be made to unblock the valve or remove any foreign bodies (e.g. lime-scale
particles) on the seal component by operating the venting mechanism several times.
If this fails then an overhaul by an installation company should be arranged. In case of damage to the
valve seat or seal then the safety valve will have to be completely replaced.
Implementation:
Installation Company
Interval:
annually
To check the back-flow valve the shut-off valve is closed and no water should escape via the open
test valve.
The operation of the storage tank takes place via the hot water valve of the control device (mixing
unit). Therefore the storage tank is permanently under pressure. In order to protect the inner boiler
from overpressure during heating-up. the excess water that arises is drained off via the safety valve.
To avoid overpressure damage to the water heater it is crucial to replace calcified safety valves. In
the event of a drop in pipeline pressure, the back-flow valve prevents the back-flow of the hot water
into the cold water pipe system thereby protecting the boiler from being heated up in the absence
of water. The storage tank can be separated from the cold water supply grid by the shut-off valve on
the water side and therefore also in terms of pressure and can be drained off via the drainage valve if
necessary.
