System Shutdown - Viessmann VITOPLEX 100?LS Installation And Service Instructions Manual

Initial start−up, inspection and maintenance
Further details regarding the individual steps

System shutdown

¨ Safety instruction
Only open the water and steam
connections and the inspection ports
after the boiler has been completely
depressurised.
Information regarding system shutdowns
If you do not require to use your
boiler system temporarily, maintain
the boiler water temperature by
means of the thermostat (standby) at
95 ºC, to prevent corrosion through
ingress of oxygen into the boiler
water.
If you want to shut down your
heating system for longer periods of
time (several months), shut it down
completely.
H Before taking the system out of use
for longer periods, we recommend
you take certain measures, e.g.
protecting the system against frost
or preserving the heating surfaces.
H Thoroughly clean the surfaces on
the flue gas side to preserve the
heating surfaces. Then conserve
these surfaces with a preserving oil
mixed with graphite.
8
(cont.)
1. Close the shut−off valves in the oil
supply pipes (at the oil tank and
filter) or the gas shut−off valve,
whichever is applicable.
2. Switch OFF the burner and the
feed water pump. Pull the
connecting plug from the burner.
3. Isolate the system from the mains
power supply.
4. Close all valves.
H For the protection of the water
side, we recommend you flood the
boiler with degassed, oxygen−free
and treated water with low salt
content and added oxygen binders
(e.g. sodium sulphite).
Then close the steam shut−off
valve.
Check the concentration of the
oxygen binder at least every month
and replenish, if necessary. When
doing this, ensure that the binder is
well−mixed with water inside the
boiler.
H Another option is that of dry
preservation, which is
recommended for shutdown
periods longer than 4 weeks.
H When there is a risk of frost, drain
the boiler and the heating system
via the drain plug.
Open the shut−off and regulating
valves as well as the air vents.