17Installation instructions VRC 430f 0020042470_01
Glossary
set-back temp
The set-back temperature is the reduced interior tem-
perature maintained by your heating system outside of
the programmed time window.
Auto_Off (operating level for heating engineer)
The control behaviour in the Automatic operating mode
for the times in which no time windows are programmed
can be defined in screen C21 "Total system parameters"
under the menu item "Mode Auto_Off". The options are
frost protection, ECO and energy sav.
– Frost protection
In the times when no time windows are programmed
the appliance is switched off. The frost protection
function (see menu) is active.
– ECO
In the times when no time windows are programmed
the appliance is switched off. The outside temperature
is monitored. If the outside temperature falls below
3 °C, the set-back temp is applied as the room target
temperature (minimum 5 °C). This target room target
value is used for control. A set frost protection delay
time (see menu) also affects the start of this control.
If the outside temperature rises to above 4 °C, the
outside temperature monitoring remains active and
the appliance is switched off.
– Set-back
In the times when no time window is programmed, the
room target temperature is set to the set-back temp
(minimum 5 °C). This target room value is used for
control.
Operator level
Used to display and set/change the basic parameters.
The setting/ parameters can be changed by the user
without any special previous knowledge and during nor-
mal operation. The heating system can continuously
adapt to the requirements of the operator by making
the corresponding basic parameter settings.
Expert technician level
Used to display and set/change specific parameters.
This level is reserved exclusively for use by the heating
engineer and is therefore protected by an access code.
Operating mode
The operating modes "Auto" (automatic), "Manual" and
"OFF" exist. You can use the operating modes to specify
how you wish your room heating or water heating to be
controlled (see operating instructions, Section 4.3.2,
Table 4.2).
DCF
The DCF radio receiver receives a clock signal and pass-
es on the time to the controller. Your controller switch-
es automatically between summer/winter time . You
only need to change the time manually if the receiver
fails to receive a signal.
Frost protection function
The frost protection function protects your heating sys-
tem and apartment from frost damage. It is also active
in the "OFF" operating mode.
The frost protection function monitors the outside
temperature. If the outside temperature falls below
3 °C, the heating pump is switched on for approx.
10 min. and then off for between 10 and 60 min. (irre-
spective of the value of the outside temperature). If the
heating flow temperature is less than 13 °C, the burner
for the appliance is switched on and the room tempera-
ture is controlled with reference to a target value of
5 °C. If the outside temperature rises to above 4 °C, the
outside temperature monitoring remains active; the
heating pump and burner are switched off.
If the outside temperature falls to below -20 °C, the
burner for the appliance is switched on directly and the
room temperature is controlled with reference to a tar-
get value of 5 °C.
Frost protection delay time
The heating control trigger via the frost protection func-
tion (outside temperature < 3 °C) can be delayed by a
specific time period (1 - 12 hours) by specifying a frost
protection delay time (heating engineer level).
The set frost protection delay time also works in the
"ECO" function in the "Auto_Off" mode (see location).
The frost protection delay time starts when the outside
temperature falls below 3 °C.
Heating circuit (HC1)
HC1 indicates heating circuit 1. This refers to the heating
of your heating system. You can use a special
designation instead of HC1 (see operating instructions
Section 4.7.5).
Appendix
Glossary
