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Flush-mount room thermostat with KNX communications, 2-/4-pipe fan coils or DX type equipment

Stock no. S55770-T104

Stock no. S55770-T104

Flush-mount room thermostat with LCD for fan coil units and compressors in DX-type equipment

  • KNX communications

  • Operating modes: Comfort, Economy and Protection

  • For heating and/or cooling applications

  • 2 or 3-position control outputs

  • Output for 1-speed or 3-speed fan

  • 2 multifunctional inputs for keycard contact, external room / return air temperature (QAH11.1, QAA32), heat / cool changeover, operation mode changeover, window contact on/off, dewpoint monitor, electrical heater enabled, fault contact

  • Automatic or manual heating/cooling changeover

  • Adjustable commissioning and control parameters

  • Minimum and maximum setpoint limitation

  • Color of housing: signal white (RAL 9003)

  • Backlit display

Application selectable:

  • 2-pipe system

  • 2-pipe system with electrical heater

  • 4-pipe system



Operating voltage

AC 230 V


50/60 Hz

Power consumption

4 VA

Positioning signal

2-position, 3-position

Control algorithm

2-point / PI

Ambient temperature, operation

0...50 °C

Setpoint setting range

5...40 °C

Measuring range, temperature

0…49 °C

Switching differential

0.5…6 K


Bus: KNX (S-mode and LTE mode with Synco 700)

Analog inputs

External room / return air temperature, Heat / Cool changeover, Operation mode changeover, Window contact on/off, Dewpoint monitor, Electrical heater enabled, Monitor input, Fault input

Analog inputs, number


Analog input, signal

NTC 3k , Switch

Relay outputs

Fan: N.O. contacts, non-floating, Valve: N.O. contacts, non-floating

Relay outputs, number


Relay output, switching voltage

AC 230 V

Relay output, switching current

5 (2) A


Flush-mounting with recessed rectangular conduit box
Fixing center 60.3 mm (BS4662)

Type of fixing

Recessed rectangular conduit box BS4662 with fixing centres of 60.3 mm (ARG71)

Degree of protection


Dimensions (W x H x D)

86 x 86 x 57 mm