Operating Instructions

2/2 A6V12064527_en--_b A5W00123798A_AB 2021-04-14 Siemens Smart Infrastructure
Operating Instructions
RDF660T
Display
Protection mode
Auto Timer mode
Comfort mode
Economy mode **
Measured room temperature,
setpoints and parameters
Current time of day
Actual room temperature
Fault indicator *
Condensation in the room *
Cooling demand / mode
Heating demand / mode
Electric heater active
Automatic fan
Low fan speed
Medium fan speed
High fan speed
Buttons are locked
Weekday 1…7
(1 = Monday / 7 = Sunday)
* Needs to be configured by your HVAC installer
** Needs to be enabled via parameter P02
Change room temperature setpoint
Press + or – buttons to increase or decrease the current room temperature setpoint for Comfort mode. The
thermostat changes to Comfort
.
The setting range is 5...35 °C, unless limited by parameters P09 and P10.
Adjust fan speed/fan mode
Press the
button to adjust the fan mode and fan speed.
In Auto mode , the thermostat automatically selects the fan speed based on setpoint and actual room
temperature. The fan is switched off (factory setting) after the room temperature reaches the setpoint.
In manual mode, the fan always runs at the speed that user selects:
Low fan speed
Medium fan speed
High fan speed
Change thermostat operating mode
Press operating mode button to change the operating mode display.
In Comfort mode , the thermostat maintains the room temperature at the setpoint which can be
readjusted using the + and – buttons.
In Economy mode , the room temperature is maintained at a lower or higher fixed setpoint ( factory-set:
15 °C,
30 °C) to save energy. Adjust parameters P11 and P12 to change the preselected setpoints. The
availability of Economy mode depends on parameter P02 or via an external signal (switch) such as keycard
or presence detector.
In Protection mode , the thermostat stops operating. However, it will operate if the room temperature is
below 8 °C (heating application) against frost (P65) and the value is adjustable.
In Auto timer mode , the thermostat automatically switches between Comfort and Economy mode
according to the time schedule.
Important: User can set Protection setpoints to OFF; the thermostat then is inactive, i.e. no protective
heating or cooling function. Risk of frost!
Change from heating to cooling mode
Changeover between cooling and heating
is either automatic using a heating/cooling changeover
sensor or a remote changeover switch or manual by pressing operating mode button .
No changeover is possible if the thermostat is configured for cooling only or heating only (see parameter
P01).
Meaning of cooling and heating symbols when displaying on LCD:
 For automatic changeover or heating only/cooling only:
- Heating valve is open
- Cooling valve is open
 For manual changeover only:
- Thermostat is in heating mode
- Thermostat is in cooling mode
Set time schedules
To adjust the time schedule, keep pressing button for 3 seconds to enter
the timer setting mode.
This mode is indicated by displaying Ax (x= auto timer 1...8) and the time
flashing.
For each timer, proceed as follows:
1. The and
symbols are displayed. Press + or – to adjust the comfort
mode start time and confirm by pressing .
2. The and symbols are displayed. Press + or – to adjust the comfort mode
end time / Economy start time and confirm by pressing .
3. Symbol will flash. Press + or – to select or deselect each day and advance
to the next day.
4. Press to confirm the settings for the actual timer and advance to the next
timer.
The thermostat will leave the timer setting mode if no button is pressed within
20 seconds. All changes made after the last press of the button are not
saved.
View the timer settings
Press the button to sequentially view the 8 auto timers.
Reload default timer settings
1. Set the thermostat to protection mode .
2. Press + and – simultaneously for 3 seconds. Release and, within 2 seconds,
press twice
Default
settings
Days Thermostat is in Comfort mode
Mo (1) – Fr (5) 6:30 – 8:30 (A1) 17:30 – 22:30 (A2)
Sa (6) 8:00 – 23:00 (A3)
Su (7) 8:00 – 22:30 (A4)
– In the remaining time thermostat is in
Economy mode.
– Timers A5…A8 are free, no default settings.
Key lock
The key symbol indicates buttons are locked.
Key lock can be configured via parameter P14.
Reminder to clean filters and for external faults
FIL *This message reminds user to clean HVAC equipment filters.
AL1 or AL2 indicates external faults.
Commissioning
User can adjust several different control parameters to adapt the thermostat to
your system and optimize control performance. User can do this during
operation via the buttons on the thermostat.
Control parameters
Proceed as follows to change the most important control parameters
1. Press the – and + buttons simultaneously for more than 6 seconds.
Release, and within 2 seconds, press + again for more than 3 seconds.
"P01" is displayed.
2. Repeatedly press the + or – button to select the required parameter.
3. Press + and – simultaneously once to enter EDIT mode. Then press + or –
button to change the value of the selected parameter and press + and –
simultaneously to save the change.
4. Repeat steps 2 to 3 to display and change additional parameters.
5. Press + or – until “End” is displayed, and then press + and – simultaneously
to exit parameter entry mode.
Setting time of day and weekday
1. Press button and the time digits start to flash. Press + or – to set the time of day. If the current time is in 24-hour format and user wishes to change to the 12-hour format, press + passing
23:59 or press – passing 00:00. Back to 24-hour format: same procedure with 11.59 PM.
2. Confirm the time of day by pressing and the weekday indicator starts to flash.
3. Press + or – to set the current weekday.
4. Confirm the current weekday by pressing .
Parameter Description Factory setting Setting range
P01 Control sequence
2-pipe = 1 [selection: 0…3]
4-pipe = 4 [selection: 2, 4]
0 = Heating only; 1 = Cooling only; 2 = H/C changeover manual
3 = H/C Changeover auto; 4 = Heating and cooling
P02 Mode selection by user via operating mode button 1
1 = Auto – Comfort – Protection; 2 = Auto – Comfort – Economy – Protection
3 = Comfort – Protection; 4 = Comfort - Economy - Protection
P04 Unit 0 0 = °C (Celsius); 1 = °F (Fahrenheit)
P05
Measured value correction (for built-in/external
sensor)
0
-5 K...5 K
P06 Standard display 0 0 = Room temperature; 1 = Setpoint
P07 Additional display information 0
0 = No display; 1 = Room temperature °C or °F; 2 = Setpoint
3 = Time of day (12 h); 4 = Time of day (24 h)
P08 Comfort basic setpoint
21 °C 5...40 °C
P09 Minimum Comfort setpoint
5 °C 5...40 °C
P10 Maximum Comfort setpoint
35 °C 5...40 °C
P11 Economy heating setpoint (WheatEco)
15 °C OFF, 5 °C…WcoolEco
P12 Economy cooling setpoint (WcoolEco)
30 °C OFF, WheatEco…40 °C
P13 *** Electrical heater in cooling mode 1 0 = Disabled; 1 = Enabled
P14 Key lock 0 0 = Unlock; 1 = Lock (all lock); 2 = Setpoint adjustable
All temperature settings are in increments of 0.5 °C. *** Parameter P13 is only displayed for application "2-pipe with electric heater".
Issued by
Siemens Switzerland Ltd
Smart Infrastructure
Global Headquarters
Theilerstrasse 1a
CH-6300 Zug
Tel. [phone]
www.siemens.com/buildingtechnologies
© Siemens Switzerland Ltd, 2020
Technical specifications and availability subject to change without notice.