Danfoss Icon2

Underfloor heating controller

Danfoss Icon2 controls hydronic underfloor heating room by room. Its Main Controller drives up to 15 actuator outputs from wired or wireless room thermostats, and joins a Zigbee 3.0 network so Edge can read and set every room through one device.

Also sold asDanfoss Icon2 Main Controller

Danfoss Icon2
  • Zigbee

Underfloor heating controller

Compatibility

Compatible with EpiSensor Edge over Zigbee.

Pair it with the Zigbee radio on an EpiSensor Gateway. Edge reads it locally on the Gateway.

Edge reads 24 values from it, listed under Interface.

Connect it with

Specifications

Icon2 is Danfoss’s room control system for hydronic floor heating and other systems with thermal actuators. The Main Controller sits at the manifold and switches one 230 V thermal actuator per output; the Advanced Main Controller has 15 outputs, and a conversion module changes them to 24 V. Room thermostats connect to it by wire or wirelessly. Danfoss makes display thermostats, a version with an infrared floor sensor, in-wall and on-wall thermostats, and a sensor with no display.1

Power
Mains. The Main Controller runs from 220 to 240 V AC and must be earthed. Wireless room thermostats and the Icon2 Sensor run on 1.5 V AAA alkaline cells.1
Advanced Main Controller
088U2110, 15 actuator outputs1
Actuator outputs
230 V thermal actuators, one per output; 24 V with conversion module 088U21401
Mains supply
220 to 240 V AC, 50/60 Hz1
Plant outputs
Pump output PWR1 (230 V, max. 100 W) and a voltage-free relay for heat demand1
Supply sensor input
PT1000, for flow temperature control1
Rooms over Zigbee
Up to 15, one endpoint each3
Setpoint range
5 to 35 °C per room, 0.5 °C steps3
Floor temperature limits
18 to 35 °C3
Controllers per system
Up to four Main Controllers, wirelessly linked1
Wireless thermostat batteries
1.5 V AAA alkaline1
Range accessories
Zigbee repeater 088U1131, external antenna 088U21411

Where it is used

  • Room temperature and setpoints across a floor-heated office, school or care home, read through one controller per manifold.

    Indoor environmental monitoring

  • Matching heat demand from the floor heating to a heat pump’s electricity and heat output, using the controller’s heat supply request.

    Heat pump performance monitoring

  • Alarming on floor sensor faults, lost thermostats and supply sensor faults from the room and system status codes.

Interface

Readings and settings, with units and ranges where Danfoss publishes them. readable, readable and writable.3

Download
ReadingUnitRange or valuesAccess
Measurements 7
Room temperaturePer room: N is the room number, 1 to 15. °C - Read only
Floor temperaturePer room: N is the room number, 1 to 15. °C - Read only
HumidityPer room: N is the room number, 1 to 15. % - Read only
Heating statePer room: N is the room number, 1 to 15. - idleheat Read only
Actuator outputPer room: N is the room number, 1 to 15. - inactiveactive Read only
Heat supply requestMain Controller: whether any room needs heat from the plant. - noneheat_supply_request Read only
Water in the pipesMain Controller: heating or cooling water. - hot_water_flow_in_pipescool_water_flow_in_pipes Read only
Controls 2
Heating setpointPer room: N is the room number, 1 to 15. °C 5 to 35 °C Read and write
System modePer room: N is the room number, 1 to 15. - heat Read and write
Settings 9
Lowest setpoint allowedPer room: N is the room number, 1 to 15. °C 4 to 35 °C Read and write
Highest setpoint allowedPer room: N is the room number, 1 to 15. °C 4 to 35 °C Read and write
Minimum floor temperaturePer room: N is the room number, 1 to 15. °C 18 to 35 °C Read and write
Maximum floor temperaturePer room: N is the room number, 1 to 15. °C 18 to 35 °C Read and write
Floor sensor modePer room: N is the room number, 1 to 15. - comfortfloor_onlydual_mode Read only
Schedule in usePer room: N is the room number, 1 to 15. - regular_schedule_selectedvacation_schedule_selected Read only
Pre-heatPer room: N is the room number, 1 to 15. - disableenable Read only
ApplicationMain Controller: the Icon2 application number set at commissioning. - 01234567and 13 more Read only
Forced heating or coolingMain Controller. - force_heatingforce_coolingnone Read only
Diagnostics 6
Pre-heat statusPer room: N is the room number, 1 to 15. - disableenable Read only
Setpoint change sourcePer room: N is the room number, 1 to 15. - manualscheduleexternally Read only
Room statusPer room: N is the room number, 1 to 15. - no_errormissing_rtrt_touch_errorfloor_sensor_short_circuitfloor_sensor_disconnected Read only
Thermostat batteryPer room: N is the room number, 1 to 15. % 0 to 100 % Read only
Main Controller statusMain Controller. - no_errormissing_expansion_boardmissing_radio_modulemissing_command_modulemissing_master_railmissing_slave_rail_no_1missing_slave_rail_no_2pt1000_input_short_circuitand 2 more Read only
Controller roleMain Controller: its role when several controllers work together. - invalid_unusedmasterslave_1slave_2 Read only

Every room property carries its room number as a suffix, for example local_temperature_3 for room 3.3

System properties carry the suffix 232, the Main Controller’s own endpoint: heat_supply_request_232, system_status_water_232 and system_status_code_232.3

temperature_N is the floor temperature and needs a floor sensor on that room’s thermostat. local_temperature_N is the air temperature.3

Commission the room thermostats before joining. Danfoss’s controller refuses to join the Ally Gateway while no room thermostats are connected to it.1

Setup

  1. Commission the Icon2 system first

    Connect the actuators, thermostats and accessories, then power up the Main Controller and link each thermostat to its outputs with the Icon2 app over Bluetooth or on the controller itself.1

  2. Open pairing in Edge

    Open pairing on the Gateway’s Zigbee network in Edge. A Zigbee 3.0 network needs the QR code in the lower left corner of the Main Controller’s front, which carries its install code.1

  3. Press OK on the Main Controller

    Press the OK button on the Main Controller to finish joining. It then sends its rooms to the network.1

  4. Check every room

    Confirm that Edge identifies it as Danfoss Icon2, then check that each commissioned room reports a room temperature. Change one room’s setpoint from Edge and confirm it on that room’s thermostat.

Common questions

Which part of Icon2 pairs with the Gateway?
The Main Controller. It joins the Zigbee network and brings every room linked to it, up to 15, as numbered endpoints. The room thermostats stay linked to the controller.13
Do I need the Danfoss Ally Gateway?
No. Danfoss documents joining Icon2 to other Zigbee-based systems: scan the QR code on the Main Controller for a Zigbee 3.0 network, then press OK. The Ally Gateway is only needed for the Danfoss Ally app.1
Can Edge read floor temperature?
Yes, for rooms whose thermostat has a floor sensor, either the optional wired sensor or the Featured thermostat’s infrared sensor. It appears as temperature_N beside the air temperature local_temperature_N.13
How do I remove it from an old Zigbee network?
Hold the > button for 15 seconds and release when the left LED blinks. Both LEDs turn red while the outputs light in sequence; when the left LED is off and the right is green, the controller has left the network.1
The controller sits in a metal cabinet. Will it reach the Gateway?
Metal blocks the signal. Danfoss sells an external antenna for the Main Controller for this case, and a Zigbee repeater to extend range to the thermostats.1

Sources

  1. Danfoss Icon2 application guide (opens in a new tab) (PDF) Danfoss
  2. Danfoss Icon2 (opens in a new tab) Danfoss
  3. Danfoss Icon2 Zigbee definition (opens in a new tab) zigbee-herdsman-converters
  4. Danfoss Icon2 device documentation (opens in a new tab) Zigbee2MQTT

Further reading

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