51/70
Siemens Building Technologies
Basic Documentation QAA73.110 Room unit
CE1P2284en
HVAC Products
Description
of the heating engineer settings
10.07.2002
4.27 Clock time master
The clock time of the QAA73.110 and the clock time of the connected boiler control can
be synchronized. In that case, one of the units will be defined as the clock time master,
and the other unit adopts the time of day from the master.
1. Press the line selection buttons to select line 96.
2. Press the + / – buttons to define the clock time master.
Setting range
Unit
Factory setting
QAA73, external
–
QAA73
The setting defines the clock time master.
Display:
QAA73
QAA73.110 is the clock time master. OpenTherm transmits the time of day to
the boiler control, either periodically or after an adjustment.
ExternallyThe QAA73.110 adopts the time of day periodically (every 5 minutes) from
the boiler control. In that case, the time of day cannot be readjusted on the
QAA73.110.
4.28 Winter- / summertime changeover
This function enables the yearly clock to automatically switch to wintertime.
1. Press the line selection buttons to select line 97.
2. Press the + / – buttons to set the date of changeover.
Setting range
Unit
Factory setting
1. Jan ... 31. Dec
dd.mm
25. March
On the Sunday following the set date, the time of day of the room unit will switch to
summertime. For that purpose, the time of day is shifted forward by one hour.
In compliance with international standards, the change from winter- to summertime is
made on the last Sunday in March, and the change from summer- to wintertime on the
last Sunday in October. The factory setting of the room unit meets this requirement as
the Sundays in question lie in the adjustable period of time between the factory setting
and the last day of the relevant month.
Description
Line 96
Effect
Description
Line 97
Effect
International standards
