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Wireless Heating and Hot Water Control Systems, Sundial RF2

Wireless Heating and Hot Water Control Systems, Sundial RF2

The Sundial RF2 systems consist of several wireless enabled components: a timer/programmer from the ST9020 series, and a combination of ...

Product Description

The Sundial RF2 systems consist of several wireless enabled components: a timer/programmer from the ST9020 series, and a combination of DT92 room thermostat and/or CS92 cylinder thermostat.
The ST9020 range is an extension to the ST9000 family to cover wireless applications. Each ST9020 product is wireless enabled, with a built in wireless transceiver. This allows it to communicate with wireless room thermostats, cylinder thermostats and other RF devices to form a complete Sundial RF2 control system that is energy efficient and compliant with Building Regulations.
The time control is mains powered and does the control and switching of the system components such as boilers, pumps and zone valves. It therefore acts as the hub of the system and once connected allows simple installation of the wireless room thermostat (DT92E) or cylinder thermostat (CS92A).
Sundial RF2 can be used to upgrade older systems that do not have boiler interlock in the form of a room thermostat or cylinder thermostat, as well as being suitable for new installations. There are 5 packs designed to cover applications with combi-boiler systems, 2-zone systems, and systems with stored hot water tanks. These systems can be extended to allow remote wireless control of valves and/or boilers using the wireless relay box BDR91T. Pack 5 also has an OpenTherm low voltage output for modulating control of the boiler.

Technical Properties

Modes of operation off/auto/once/cont
Time setting resolution 1 min. for clock, 10 min. for programs
Approvals CE
ErP Class IV
Control output relays
Switch function/capacity contact output 230Vac, 3 A resistive, 3 A inductive ratings
LED functions
  • ST9020: indicates on/off status of zone control relays
  • CS92: used for RF binding, indication of signal strength and fault conditions
Protection class IP30
Terminal max. wire size 2,5 mm2
Power supply
  • time control ST9020: 230 Vac / 10 VA
  • thermostats DT92/CS92: battery-powered, 2 x 1.5 V AA Alkaline cells
Memory back-up
  • all products: settings and parameters stored in NVRAM
  • ST9020: battery maintains factory-set date and time for installation and backup for up to 9000 hours of power cuts
  • ST9020: super-capacitor provides emergency backup for more than 1.5 hours
Additional Descriptions All products have:
  • 2-way RF communication
  • installer mode
  • optimization (optimum start, delayed start, optimum stop)
  • service mode with telephone number display and PIN-code access protection
  • holiday mode
  • override buttons extra hour and override

Related Material


Product Type Application information
Sundial RF2 Pack 1

Combi boiler ST9120C+DT92E
Sundial RF2 Pack 2

System boiler, with stored DHW and existing wired DHW thermostat ST9420C+DT92E
Sundial RF2 Pack 3

System boiler, with stored DHW without existing wired DHW thermostat ST9420C+DT92E+CS92A
Sundial RF2 Pack 4

Stored DHW systems ST9120C+CS92A
Sundial RF2 Pack 5; ErP Class V

Combi boiler with 2 heating zones ST5020+DT92E+DT92E

Accessories and replacement parts

Spare units

Image Description Product Type Downloads
7 day single channel wireless timer ST9120C1003  
7 day 2 channel programmer ST9420C1008  
7 day 2 zone timer ST9520C1005  
Digital Room sensor/setpoint adjustment unit with ECO DTS92E1020  
Wireless DHW thermostat CS92A1007  
Wireless relay box BDR91T1004