RDF20U Room Temperature Controller with LCD
Technical Instructions
For Two-Pipe Fan Coil Units with Electric Heat
Document Number 155-334
September 27, 2007
Siemens Industry, Inc.
Page 11
Specifications,
Continued
Environmental Conditions
Operation
Temperature
32°F to 122°F (0°C to 50°C)
Humidity
<95% rh
Transport and storage
Temperature
-13°F to 158°F (-25°C to 70°C)
Humidity
<95% rh
Agency Approvals
UL Listing
UL 873
General
Connection terminals
Solid wires or prepared stranded
wires 2 × 16 AWG or 1 × 14 AWG
Weight
0.55 lb (0.25 kg)
Housing front color
White (RAL 9003)
Wiring Terminals
Figure 9. Wiring Terminals.
1, 2
24 Vac, negative
3
24 Vac, positive
9
Return air temperature
sensor
8
Measuring neutral
7
Changeover sensor
D1,GND
Potential-free operating mode
changeover switch (operating action
can be selected)
12
Control output, Fan speed I, 24 Vac
11
Control output, Fan speed II, 24 Vac
10
Control output, Fan speed III, 24 Vac
4
Control output, Valve 24 Vac
5
Control output, Valve 24 Vac
6
Control output, Electric heat 24 Vac
Wiring Diagrams
Figure 10. Two-Pipe Fan Coil Units with
Electric Heat.
B1
Return air temperature sensor
(QAH11.1)
B2
Changeover sensor (temperature
sensor QAH11.1)
E1
Electric heat
M1
3-speed fan
N1
Room temperature controller
RDF20U
S1
External operating mode
changeover switch
SN
24 Vac, negative
SP
24 Vac, positive
Y1
Zone valve
