Zehnder Rittling Timer RF Manual page 16

Operation
The Timer RF is fitted with 4 buttons:
Button Printing
1 10 min.
2 30 min.
3 60 min.
4 timer OFF Stop temporary ventilation
16 - EN
Function
Ventilate for 10 minutes in the
highest setting
Ventilate for 30 minutes in the
highest setting
Ventilate for 60 minutes in the
highest setting
in the highest setting. The
ventilation unit then returns
to the ventilation setting
previously selected on the other
control units. When the Timer
RF is used in combination with
the RFZ remote control, the
ventilation unit will operate in
setting 1 (low).