Baxi Power HT 1.850 Installation, Operation And Maintenance Manual page 94

12.5 CONNECTING THE OUTDOOR TEMPERATURE SENSOR PROBE
IT
The SIEMENS model QAC34 outdoor temperature sensor probe (optional accessory) must be connected to
AT
terminals 7-8 of terminal board M2 in figure 8.
The procedures for setting the gradient of the temperature curve "kt" vary depending on the accessories con-
nected to the boiler.
GB
a) Without QAA73 room temperature regulator:
The temperature curve "kt" must be selected by setting parameter H532 as described in section 14 "setting the
boiler parameters".
See graph 1 for selecting the curve referred to a room temperature of 20°C.
The chosen curve can be shifted by pressing the
the value displayed by pressing the
in graph 3 refers to the curve Kt=15.
Increase the value displayed if the room temperature required is not reached inside the premises for central
heating.
b) with QAA73 room temperature regulator:
The temperature curve "kt" must be selected by setting parameter 70 "HC1 curve" of the QAA73 room tem-
perature control device as described in section 12.4 "QAA73: parameters which can be set by the installation
(service) engineer".
See graph 4 for selecting the curve referred to a room temperature of 20°C.
The curve is shifted automatically on the basis of the room temperature set using the QAA73 climate control.
If the system is divided into zones, the temperature curve "kt" relating to the part of the system not controlled
by the QAA73 must be selected by setting parameter H532 as described in section 17 "setting the boiler pa-
rameters".
IMPORTANT: For systems divided into zones, parameter 80 "HC2 gradient", which can be set on the
QAA73 temperature regulator, must be set as —.- "not active" (see section 12.4).
Graph 4
and
TM = Flow temperature
Te = Composite outside temperature
Graph 2 Sth = Kt Curve
TM = Flow temperature
Te = Composite outside temperature
INSTRUCTIONS PERTAINING TO THE INSTALLER
(2), button (2) on the boiler control panel, and modifying
. keys. See graph 2 for curve selection. (The example show
94
Graph 3