14
SERVICE BY THE HEATING SPECIALIST
DHC 23
■■
Special functions and operating parameters
for DHC 23-1
If the DHC 23 is controlled at the input TW by a system other than the remote control
TF 26, it must be possible to ignore a signal applied at this input. Activating this
function has the effect that the applied signal is taken into account only up to the next
switching time and then ignored.
The inlet temperature in the external domestic hot water heat exchanger can be limited
upwards to prevent calcification. This function is active only in layered domestic hot
water storage tank operation (DHC 23-1).
In problematic systems, the switching difference between cut-in and cut-off temperature
can be changed.
This switching difference influences the duration of the charging pump run-on in
layered domestic hot water storage tank operation.
During domestic hot water charging, the return temperature limitation can be
cancelled. The higher values for the return temperature allowed for this special case
are determined here
The entry of 0 min. (time set in the factory) is treated as absolute domestic hot water
priority: The heating circuit pump is switched off as long as domestic hot water is being
charged. However, should the heating circuit cool down too much because of domestic
hot water charging, the DHC 23 can be set to interrupted domestic hot water priority by
changing the value from 0 min. (e.g. to 15 min.). The domestic hot water charging
pump and heating circuit pump then alternate and are operated in each case as long
as entered here (e.g. 15 min.).
Overwrite TF 26 status
(8)
Maximum inlet temperature in the
WW heat exchanger VF
1
(9)
Layered domestic hot water stora-
ge tank switching difference
(9) + ( )
Switching difference for domestic
hot water pump run-on
(A) + ( )
Maximum district heating return
temperature with sole domestic hot
water charging
(B) + ( )
Time interruption of domestic hot
water priority
(C) + ( )
10878_BDA_DHC23_engl_neu 06.09.1999 13:50 Uhr Seite 16
