WDC weather compensated controllers are intended for the regulation of room heating and hot water production in single-family houses. They allow for the regulation of one or two heating circuits, switching between heating sources, and the protection of the return line during the charging of the supply device. They are used for heating systems with one or two furnaces, a heat pump, a hot water buffer tank, and a solar system.


Application WDC20

  • Regulating radiator space heating system
  • Regulating floor heating or cooling system
  • Regulating convector heating or cooling system
  • Regulating wall or ceiling heating or cooling system
  • Hot water preparation


Advantage WDC20

  • 52 preset hydraulic diagrams,
  • time-program specific space heating or cooling
  • time-program specific sanitary water heating
  • hot sanitary water preparation using a solar system,
  • regulation of heating systems with reservoir,
  • the option of connecting 2 room units,
  • the BOOST function for space heating,
  • integrated functions for solar system protection,
  • 13 language user interface,
  • startup wizard for an easy and quick startup of the device,
  • diagnostics of operation by prompting to errors and exceeded temperatures,
  • the SeltronHome platform connectivity allowing remote control via smartphone or tablet.

Radiator room heating system control   
Floor heating or cooling system control   
Convector heating or cooling system control   
Wall or ceiling heating or cooling system control   
Domestic hot water heating   
No. of preset hydraulic schemes71752
No. of room units222
No. of mechanical relays667
No. of solid state relays11
No. of analogue outputs (0÷10 V or PWM) for the control of the circulation
pump or an energy source
No. of temperature sensor inputs777
BUS option – the interconnection of WDC controllers and connection with other Seltron controllers   
Control of a heating system with radiators   
Floor heating or cooling system control   
Convector heating or cooling system control   
Wall or ceiling heating or cooling system control   
Domestic hot water heating system control   
Direct circuit   
Mixing circuit   
Direct and mixing circuit  
Two mixing circuits 
Domestic hot water heating   
Switchover between direct heating circuit and domestic hot water heating   
Domestic hot water circulation   
Automatic switchover between heat sources 
Control of the supply line constant temperature   
Single-stage storage tank loading 
Solid fuel boiler   
Solid fuel boiler with a pellet burner 
Liquid fuel boiler   
Liquid fuel boiler with a two-stage burner   
Combined boiler 
Gas flow boiler 
Heat pump 
Storage tank   
Auxiliary heating with electricity   
Solar collectors  
With a primary heating source   
With a storage tank   
Using a solar system  
Room heating or cooling according to the time programme   
Automatic winter/summer mode switchover   
PARTY function – activation of the comfort operation mode   
ECO function – activation of the economy operation mode   
HOLIDAY function – activation of the operation mode during the holiday season   
Domestic hot water heating according to the time programme   
One-time domestic hot water heating   
BOOST function for intense room heating   
Function for screed drying   
Anti-legionella protection (for a controlled energy source)   
Storage tank overheating protection   
Boiler overheating protection   
Collector frost protection  
Forced pump start at the highest collector temperature  
Switching off of the collectors when the safety temperature has been exceeded  
Solar system protection when collectors are overheating  
Storage tank recooling to the desired temperature  
Periodic starting up of pumps and mixing valves during a period of inactivity   
Graphic display of temperatures according to days of the last week   
Detailed display of temperatures for the current day   
Notifications on the activated protection functions and warnings about system
Possibility to simulate sensors and analyse the system operation   
With a separate dedicated cable, the controller can be connected to a computer   
Connectivity to the SeltronHome platform providing remote control using a smartphone or tablet   
Wizard for an easy and quick device start-up   
13-language user interface:
Languages: EN, DE, FR, NL, PL, ES, SL, IT, CS, LT, GR, HU, HR
Setting up the operation by selecting the hydraulic scheme   
“Help” button for quick help with the setup   
Graphically adjustable time programmes   
Option to simulate the system operation   
Logging and display of changes made to the setup   
Option for retrieval of the basic setup in the event of data loss or unwanted changes   
Option for programming free outputs   
Possibility of wall or DIN rail installation   
Simple installation and connection   

Technical specificationsWDC20
Backlit graphic displayyes
Operating hours meteryes
Weekly program timeryes
Connection voltage230 V~, 50 Hz
Own consumption2.5 W
Energy consumption in the standby modeMax. 0.5 W
No. of inputs7 pcs temperature sensor (Pt 1000)
No. of outputs7 pcs mechanical
1 pc electronic
2 pcs PWM or analogue 0÷10 V
(Y1, Y2)
Relay outputs4 (1) A~, 230 V~
Triac output1 (1) A~, 230 V~
Clock power supplyBattery CR2032 (Li-Mn) 3 V
Clock accuracy+/-1 s (24 h) at 20 °C
Degree of protectionIP20 according to EN 60529
Safety classI according to EN 60730-1
Operation mode1B according to EN 60730-1
Type of temperature sensorsPt1000 or KTY10
Operation mode3-point PID
Housing materialASA – thermoplastic
Permissible ambient temperature5÷40 °C
Storage temperature-20÷65 °C
Product weight450 g
No. of pieces in the packaging unit6 pcs
Electrical connection