Siemens RDX33.21 User manual

N3075en
17.04.2009 Building Technologies
3075
RDX33.21, RDX43.2
Room temperature
controllers with LCD and
7-day time switch
RDX33..
RDX43..
For release of a heat pump or control of actuating devices
in heating or cooling mode
•Operating modes: Auto Timer, Comfort, Energy Saving, and Protection
•Potential-free output (ON / OFF) for release of a heat pump or control of
actuating devices
•Potential-free output (ON / OFF) for selection of heating or cooling
•Output for control of auxiliary electric heating (RDX43.2)
•Manual heating / cooling changeover
•8 programmable time switches
•Selectable commissioning and control parameters
•Selectable display of room temperature or setpoint
•Minimum and maximum setpoint limitation
•Operating voltage: Batteries DC 3 V (RDX33.21)
AC 230 V (RDX43.2)

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Use
For control of the room temperature in individual rooms or zones that are heated or
cooled by a heat pump or via actuating devices.
The room temperature controller…
•controls release of the heat pump’s compressor or actuating devices
•switches an auxiliary electric heater
Suited for systems with manual H/C changeover.
Functions
•Manual H/C changeover by pressing the respective button
•Room temperature control with built-in sensor
•
Selection of operating mode via button
•Auto Timer mode with 8 programmable time switches for changeover between Com-
fort mode and Energy Saving mode
•Outputs for release of heat pump and for control of actuating devices in heating or
cooling mode (ON / OFF). Output for auxiliary electric heater
Controller
The controller acquires the room temperature via its built-in sensor and maintains it at
the adjusted setpoint.
The switching differential is 2 K in heating mode and 1 K in cooling mode (adjustable
via parameters P08 and P09).
The display shows the acquired room temperature or the setpoint of the current operat-
ing mode. This can be selected via parameter P15. Factory setting is display of the
current room temperature.
The heating and cooling symbols on the display show the system’s operating
state. Symbol shows when the auxiliary electric heater is in operation.
Symbol cindicates when the heat pump’s compressor is on.
If required, room temperature and setpoint can also be displayed in °F in place of °C.
This is made by changing parameter P14.
Operating modes
The following operating modes are available by pressing the respective button:
In Auto Timer mode AUTO, the controller switches automatically between Comfort mode
and Energy Saving mode according to the 8 programmed time switches. The controller
displays the symbol of Auto Timer mode AUTO and that of the current operating mode,
either Comfort mode or Energy Saving mode .
In Comfort mode , the controller maintains the setpoint, which can be adjusted via the
buttons.
For energy saving purposes, the setpoint setting range can be limited to a minimum
(parameter P05) and a maximum (parameter P06).
Temperatue control
Display
Auto Timer mode
Comfort mode
Energy saving tip
Setpoint limitation

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•If the minimum limit P05 is set lower than the maximum limit P06, both heating and
cooling are adjustable between these 2 limits.
•For heating or cooling applications:
– The setting range in cooling mode is from P05…40 °C instead of 5…40 °C
– The setting range in heating mode is from 5…P06 °C instead of 5…40 °C
Examples Heating or cooling
P05 < P06
5°C 40°C25°C18°C
P06P05
Cooling setpoint adjustable 18…25 °C
Heating setpoint adjustable 18…25 °C
P05 ≥P06
5°C 40°C25°C21°C
P05P06
Cooling setpoint adjustable 25…40 °C
Heating setpoint adjustable 5…21 °C
The setpoints for Energy Saving mode can be adjusted via control parameters P01
and P02.
In Protection mode , the controller monitors the setpoints adjusted for heating and
cooling. If the room temperature exceeds or falls below the setpoint, the setpoint for
Protection is maintained (this independent of the manual H/C changeover status).
These setpoints can be adjusted via control parameters P03 and P04. The factory set-
ting for heating in Protection mode is 8 °C.
P05 < P06
P05 ≥P06
Energy Saving mode
Protection mode

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Control sequences
On Q33-Q34 Q13-Q14
WW
On Q13-Q14
W
= =
= =
= =
Application with heat pump for heating or cooling
:
W Room temperature setpoint
WD Switching differential between heating and auxiliary electric heating
SDH Switching differential heating
SDC Switching differential cooling
When used in connection with a heat pump, output Q13-Q14 (NO contact) must be
connected to the compressor’s control input.
Output Q21-Q22-Q24 must be connected to the compressor’s H/C control input.
Output Q33-Q34 (NO contact) is for connection to an auxiliary electric heater
(RDX43.2).
Button is used for manual changeover from heating to cooling, or vice versa. The
factory setting of the changeover contact is “Open“ for heating and can be changed to
”Closed” for heating using parameter P18.
To avoid damage to the compressor during H/C changeover, a minimum compressor
on / off time can be adjusted via parameters P11 and P12. The factory setting for the
minimum on time is 1 minute and for the minimum off time 3 minutes.
Legend
Heating / cooling mode
Compressor on time

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Output Q33-Q34 is for connection to the auxiliary electric heater which is only available
in heating mode, provided parameter P16 is set to 1 (enable). The minimum on time
can be changed via parameter P13 (factory setting is 1 minute).
Auto Timer mode
The controller provides an Auto Timer mode with 8 programmable time switches. Each
time switch can be assigned one or several days. In this mode, the controller switches
automatically between Comfort mode and Energy Saving mode according to the pro-
grammed time switches.
Auto timer in Comfort mode Auto timer in Energy Saving mode
Each time switch has a start time and end time for Comfort mode which can be applied
to several weekdays.
To set the time schedule, keep button depressed for 3 seconds to go to the pro-
grammable timer setting mode. This mode is indicated by displaying Ax (x = auto timer
1...8) and the time of day --:-- blinking.
For each time switch, proceed as follows:
1. Symbols and are displayed. Press or to set the Comfort mode start time
and confirm by pressing .
2. Symbols and are displayed. Press or to set the start time for Comfort
mode or Energy Saving mode and confirm by pressing .
3. Symbol
1will flash. Press to select or to deselect each day and advance to
the next day. Confirm setting for actual timer by pressing and advance to
the next timer.
The controller leaves the programmable time switch setting mode if no button is
pressed within 20 seconds. All changes made after the last press of will not be
saved.
Auxiliary electric heater
RDX43.2
Setting the time
switches

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Press to sequentially review the 8 time switches.
Time switches A1…A4 have the following factory settings:
Day(s) Times of day when controller is in Comfort mode
Mo (1) – Fr (5) 06:30 – 08:30 (A1) 17:30 – 22:30 (A2)
Sa (6) 08:00 – 23:00 (A3)
So (7) 08:00 – 22:30 (A4)
- During remaining times, controller is in Energy Saving mode
- Time switches A5…A8 are free (no factory settings made)
The settings of the time switches can be changed to suit individual needs. The factory
settings can be retrieved any time:
1. Set the controller to Protection mode .
2. Press and simultaneously for 3 seconds. Release the buttons and, within 2
seconds, press 2 times.
The display shows “8888“ during this process.
In the second case, or when several time switch sequences overlap, the resulting out-
put is the OR combination of the Comfort mode time of all time switches.
The 7-day
time
switch
supports
the 12-
hour and
24-hour
format.
Parameter P17 = 0 (12 h) or = 1 (24 = factory setting).
1. Keep the button depressed until the time digits start blinking.
Press or to set the time of day.
2. Confirm the time of day by pressing and the weekday indicator starts blinking.
3. Press or to set the current weekday.
4. Confirm by pressing .
In the event of a power failure, the time, date, last operating mode, last heating/cooling
changeover status, setpoint and auto timer program will be stored. When power re-
turns, this time reappears and starts running again. The time display blinks to indicate
that there was a power failure. Blinking stops when the time and the day are confirmed
by pressing , or when the time is readjusted by following the above procedure.
Replace / remove battery when the “low battery” symbol is activated. The time, date,
last operating mode, last heating/cooling changeover status, setpoint and auto timer
program will be stored.
Error handling
If the room temperature is out of the measuring range (above 50 °C or below 0°C), the
display shows the limiting temperature in blinking figures (e.g. 50 °C or 0 °C).
Should the built-in sensor become defective, the display will show “Err” blinking to draw
the user‘s attention.
Viewing the time
switches
Factory settings of
time switches
Retrieving the factory
settings
Overlapping of time
switch sequences
7-day time switch
Setting the clock
Power failure
Symbol “low battery”
Temperature out of
measuring range
Failure of built-in
sensor
A1=09:00-22:00
A2=12:00-20:00
09:00 12:00 20:00 22:00
Resulting output
= 09:00-22:00

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Control parameters
A number of control parameters can be readjusted to optimize the control performance.
These parameters can also be set during operation without opening the unit. In the
event of power failure, all control parameter settings will be maintained.
The parameters can be changed as follows:
1. Set the controller to Protection mode .
2. Press and simultaneously for 3 seconds. Release the buttons and, within
2 seconds, press again for 3 seconds. The display will show “P01“.
3. Select the required parameter by repeatedly pressing and .
P01 P02 P18
+
-
+
-
+
3075Z03
+
-
4. By pressing and simultaneously, or by pressing , the current value of
the selected parameter appears, which can be changed by repeatedly pressing
or .
5. 5 seconds after the last press of a button, or by pressing and simultane-
ously, the value will be stored.
6. If you wish to display and change additional parameters, repeat steps 3
through 5.
7. 10 seconds after the last display or setting, all changes will be stored and the
controller returns to Protection mode.
The factory setting of the control parameters can be retrieved as follows:
1. Set the controller to Protection mode .
2. Press and simultaneously for 3 seconds.
Release the buttons and, within 2 seconds, press the
operating mode button 2 times.
The display shows “8888“ during this process.
Parameter settings
Parameter reset

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Parameter Factory setting Setting range in increments of ..K/..min RDX33 RDX43
P01 Setpoint for heating in Energy Saving mode (W heat Eco) 16 OFF, 5 °C…W cool Eco, 0.5 K
P02 Setpoint for cooling in Energy Saving mode (W cool Eco) 28 OFF, W heat Eco…40 °C, 0.5 K
P03* Setpoint for heating in Protection mode (W heat PROT.) 8 °C OFF, 5 °C…W cool PROT.,0.5 K
P04* Setpoint for cooling in Protection mode (W cool PROT.) OFF OFF, W heat PROT. …40 °C, 0.5 K
P05 Min. setpoint limitation in Comfort mode (W min Comf.) 5 °C 5…40 °C, 0,5 K
P06 Max. setpoint limitation in Comfort mode (W max Comf.) 35 °C 5…40 °C, 0.5 K
P07 Sensor calibration 0 K -3…+3 K, 0.5 K
P08 Switching differential in heating mode SDH 2 K 0.5…+4 K, 0.5 K
P09 Switching differential in cooling mode SDC 1 K 0.5…+4 K, 0.5 K
P10 Setpoint differential between heating and auxiliary heating WD2 K 0.5…+5 K, 0.5 K X
P11 Min. compressor on time (Q14) 1 min. 1…10 minutes, 1 min.
P12 Min. compressor off time (Q14) 3 min. 1…10 minutes, 1 min.
P13 Min. hold time of auxiliary heating 1 min. 1…10 minutes, 1 min. X
P14 Selection of °C or °F °C C or °F
P15 Display of room temperature or setpoint ON OFF: Setpoint
ON: Room temperature
P16 Auxiliary heating in heating mode 1: Enable 0: Disable
1: Enable X
P17 12- or 24-hour format 1: 24 h 0: 12-hour format
1: 24-hour format
P18 Acting direction of H/C changeover signal Q21-Q22 0: 0: Open (heating), closed (cooling)
1: Closed (heating), open (cooling)
P03*/P04*: P04 is at least min. 5 K higher than P03 X Not available
Type summary
Product No. Features
RDX33.21 Room temperature controller with outputs for compressor and H/C
changeover, operating voltage DC 3 V (battery-powered)
RDX43.2 Room temperature controller with outputs for compressor, H/C
changeover and auxiliary electric heating, operating voltage AC 230 V
Equipment combinations
Description Product No. Data Sheet
Electromotoric 2-position valve with actuator MVI…/MXI… 4867
Electromotoric 2-position actuator SFA21... 4863
Thermal actuator (for TRVs) STA21... 4893
Thermal actuator (for small valves 2.5 mm) STP21... 4878
Control parameters for RDX33.21 and RDX43.2

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Accessories
Description Product No.
Adapter plate 120 x 120 mm for recessed conduit boxes 4“ x 4“ ARG70
Adapter plate 96 x 120 mm for recessed conduit boxes 2“ x 4“ ARG70.1
Adapter plate 112 x 130 mm for surface wiring ARG70.2
Ordering
When ordering, please give description and product No.:
E.g. room temperature controller RDX33.21
Valve actuators are to be ordered as separate items.
Mechanical design
The controller consists of 2 parts:
•Plastic housing which accommodates the electronics, the operating elements and the
built-in room temperature sensor
•Mounting base
The housing engages in the mounting base and snaps on.
The base carries the screw terminals.

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1.5V
'AA'
1.5V
'AA'
+-
Operating elements
1 Buttons + and - for adjusting the setpoints, the control parameters, the days of
week, and the time of day
2 Button for selecting the mode of operation:
Protection mode
Comfort mode
Energy Saving mode
AUTO Auto Timer mode
3 Button for manual H/C changeover
4 Button for time of day and weekday settings in automatic time switch program
5 Button for selecting and setting the 8 time switches
6 Button for confirmation
Display
7 Day of week 1...7 (1 = Monday / 7 = Sunday)
8 Current room temperature, room temperature setpoint in °C or °F
9 Cooling mode
10 Auxiliary electric heating ON
11 cCompressor ON
12 Symbol for display of current room temperature
13 Time of day in hours and minutes (12- or 24-hour format)
14 Symbols:
Battery exchange
Protection mode
Comfort mode
Energy Saving mode
AUTO Auto Timer mode
15 Battery compartment (only with RDX33.21)
Setting elements,
operating elements
and display
Legend