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distribution of the heating power seems to be optimal.
Setting the offset does not change the displayed per
centage of the valve opening (valve position). The off
set value only influences the slope of the valve char
acteristic.
At a control value of 10% given by the heating control a
valve with a positive offset is opened wider than a valve
with a negative offset, although the displayed value is 10%
for both valves.
11. Replacing the battery
a) “FHT8R” heating control
If the battery symbol (“
“) is displayed on the LC display,
the battery voltage is low and they have to be replaced.
In addition, the heating control generates an acoustic alarm
every 2 minutes.
At night the acoustic alarm is not generated, but only during
the following three periods of time:
• from 10.00 hrs to 11.00 hrs
• from 17.00 hrs to 18.00 hrs
• from 21.00 hrs to 22.00 hrs
Proceed as follows to replace the batteries:
• Take the heating control off the wall holder and open the
cover of the battery compartment (slide down).
• Remove the empty batteries from the battery compart
ment and dispose of them according to applicable envi
ronmental regulations
• Insert two new LR6 (Mignon/AA) batteries; pay attention
