Page 44 - Advanced Course

KNX ADVANCED COURSE

To achieve a uniform distribution of heat
in the room, the heater should be placed
in the coldest place. This is under the
window in most cases. The heater
should at least be as wide as the
window.
Note: All the pipes of the wiring system
should be carefully and sufficiently
insulated. In well-insulated buildings,
pipes without sufficient insulation can
already heat up the rooms (when the
angle-type valve is closed). Closed-loop
control is then no longer possible.
Caution: When using a room
temperature controller, no additional
unregulated heating systems may be
located in the room!

Figure 17: Installation of the heaters and temperature sensors
Heating Control
Various control systems are possible here. The necessary fail-safe circuits (e.g. for the
boiler) are not taken into account as they must be guaranteed by the device
manufacturers.
Let us look at typical circuits for a hot water system with a single energy source (compare
with Diagram 3):

Control options according to sensors
Table 5

Control option Comment
Control dependent on room Disadvantage is that other rooms are
temperature dependent on the reference room
Individual room temperature control Each room is controlled individually

Disadvantage is that you have no
Control dependent on external information about the building
temperature
temperature

External temperature and control Advisable if other rooms are used like the
value of room temperature reference room

External temperature and control via Heat requirement is detected
the spread

Home and Building Management Systems KNX Association
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