Additional Maintenance Information; Terminology - Viessmann VITOCROSSAL 300 Operating Instructions Manual

Maintenance

Additional Maintenance Information

Danger of freezing
If the system is subject to freezing temperatures and
is not filled with antifreeze for protection, the system
including the boiler must be drained of water. The valve
before automatic feed valve (if installed) must be closed.
All other valves, air vents and drain valves must remain
open.
Long periods of shut-down
In case the heating boiler is shut down for an extended
period of time, i.e. after the heating season, the combustion
chamber, the flue gas collector and the vent pipe should
be properly cleaned to avoid corrosion. The heating
system can stay filled and under pressure. The remaining
condensate should be removed from the flue gas collector
by means of the inspection opening.

Terminology

Setback mode (reduced heating mode)
See "Reduced heating mode".
Operating program
You define the following with the operating program:
H Central heating and DHW heating
or...
H Only DHW, no central heating
or...
H Only frost protection for the boiler and the DHW tank
is active. No central heating, no DHW heating
Note: No operating program is available for central
heating without DHW heating. When you want
central heating, hot water is generally also required
(winter mode).
Operating status
In the operating program "Heating and DHW", the
operating status changes from "Standard heating mode"
to "Reduced heating mode" and vice versa. The times at
which the operating status is changed over are defined
by you when setting the time program.
Extension kit for heating circuit with mixing valve
Assembly (accessory) for controlling a heating circuit
with mixing valve. See "Mixing valve".
Underfloor heating
Underfloor heating systems are slow, low temperature
heating systems and only respond very slowly to short
term temperature changes.
Therefore, heating to the reduced room temperature at
night and enabling "Economy mode" during short
absences do not result in significant energy savings.
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Vitocrossal 300 CA3 Series 2.5 to 6.0 Operating
Water quality
The lifetime of the entire heating system is influenced by
the water quality. A water treatment system will protect
against damages caused by corrosion and lime formation.
Hard water conditions (i.e. calcium carbonate) must be
avoided as it will cause deposits to accumulate on the
heat exchanger surfaces.
If in any doubt about the water quality, please have a
proper water analysis done. Check with regional chemical
suppliers for boiler water treatment or with Viessmann
Manufacturing Company Inc. directly.
Heating mode
Standard heating mode
For periods when you will be at home during the day,
heat your rooms to the standard room temperature.
Set the periods (time phases) using the time program
for central heating.
Open source licenses
The programming unit firmware contains open source
software components. Such software is released under
an open source licence and thus available to everyone.
The full text of the licence can be displayed using the
identically named menu point.
Reduced heating mode
For periods when you will be absent or during the night,
heat your rooms to the reduced room temperature.
Set the periods using the time program for central
heating. With underfloor heating systems, reduced heating
mode only yields limited energy savings (see "Underfloor
heating system").
Room temperature-dependent heating mode
In room temperature-dependent mode, the supply
temperature is controlled according to the room
temperature.
More heat is made available at a lower room temperature
than at a higher one. The room temperature is captured
and transmitted to the control unit by a sensor.
The sensor is fitted in the room. The supply temperature
is regulated independently of the outdoor temperature.
Weather-compensated heating mode
In weather-compensated mode, the supply temperature
is controlled according to the outdoor temperature.
More heat is made available at a lower outdoor
temperature than at a higher one. The outdoor
temperature is captured and transmitted to the control
unit by a sensor.
The sensor is fitted to the exterior of the building.