Siemens RDF400 User Manual

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Siemens RDF300…/RDF340.../RDF400… Basic Documentation CE1P3076en
Building Technologies 4BFunctions 28 Aug 2008
Use with one or two valves for heating and cooling, heating/cooling with
changeover, heating only, or cooling only.
Use with one 1-stage compressor for heating and cooling, or cooling only, or
heating only.
Thanks to a flexible fan control, the RDF3xx / RDF4xx can also be used in
universal applications, e.g. fan coil-based cooling and floor heating, or chilled
ceiling and electrical heater etc. See also section 4.8 “Fan control”.
4.5 Additional features
The water temperature acquired by the changeover sensor (QAH11.1 + ARG86.3)
is used to change over from heating to cooling mode and vice-versa. When the
water temperature is above 28 °C (parameter P37), the controller changes over to
heating mode, and to cooling mode when below 16 °C (parameter P36). If the
water temperature is between the 2 changeover points immediately after power up,
the controller starts in heating mode.
The water temperature is acquired at 30-second intervals and the operating state is
updated accordingly.
16
M
T
w
[°C]
28
M Operating mode Cooling mode
T
w
Water temperature Heating mode
The QAH11.1 cable temperature sensor for automatic heating/cooling changeover
can be replaced by an external switch for manual, remote changeover:
3076Z03
X2
M
T
X2
M
QAH11.1
T °C
Contact open  heating mode
Contact closed  cooling mode
The sensor or switch can be connected to the input terminal of X2 (factory setting)
or X1 depending on the commissioning of inputs X1 and X2. See also section 4.9
“Multifun
ctional input”.
The controller acquires the room temperature via built-in sensor, external room
temperature sensor (QAA32), or external return air temperature sensor (QAH11.1)
connected to multifunctional input X1 or X2.
Inputs X1 or X2 need to be commissioned accordingly. See section 4.9 “Multi-
func
tional input”.
Water-based fan coil
application
Compressor-based
application
Universal applications
Automatic H/C
changeover
Remote heating/
cooling changeover
External / return air
temperature sensor

Siemens RDF400 Specifications

General

Brand	Siemens
Model	RDF400
Category	Temperature Controller
Language	English