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Room thermostat with KNX communications and built-in humidity sensor and humidity control, AC 24 V, for fan coil units and universal applications, heat pump, fan (1-/ 3-speed, DC), valves (2-point, DC)

Stock no. S55770-T347

Stock no. S55770-T347

  • KNX communications

  • For applications with DC control outputs and DC or 3-speed fan output

  • For applications with 2-position control output with DC fan output

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

  • Operating modes: Comfort, Economy and Protection

  • Automatic or manual EC fan or 1-/3-speed

  • Automatic or manual heating / cooling changeover

  • Adjustable commissioning and control parameters

  • Minimum and maximum setpoint limitation

  • Backlit display

  • Built-in humidity sensor and humidity control

Application selectable:

  • 2-pipe system

  • 2-pipe system with electrical heater

  • 2-pipe system and radiator / floor heating

  • 4-pipe system

  • 2-stage heating or cooling system





Operating voltage

AC 24 V


50/60 Hz

Power consumption

2 VA / 2 W

Positioning signal

DC 0…10, 2-position V

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

Heating: 0.5…6 K
Cooling: 0.5…6 K


Bus: KNX (S-Mode und LTE-Mode mit Synco 700)

Analog inputs

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

Analog inputs, number


Analog input, signal

NTC 3k , Switch

Analog outputs

Valve, el. heater: 2, Fan: 1 (ECM)

Analog outputs, number


Analog output, signal

DC 0...10 V

Analog output, current

Max. ±1 mA

Digital inputs, number


Relay outputs

Valve, compressor or el. heater: 2 outputs, 2-position, Fan: 1- or 3-speed

Relay outputs, number


Relay output, switching voltage

AC 24...230 V

Relay output, switching current

5 (4) A

Mounting position

Wall mounting


Wall mounting with screws

Type of fixing

Wall mounting with screws

Degree of protection


Dimensions (W x H x D)

93 x 128 x 30.8 mm