Aqara WT-A03E

Radiator thermostat

Aqara’s Radiator Thermostat W600 is a battery-powered valve head for wet radiators. It runs on Zigbee or Thread, sets room temperature in 0.5 °C steps from 5 to 30 °C and fits M30 × 1.5 valves directly or through six supplied adapters.

Also sold asAqara Radiator Thermostat W600

Aqara WT-A03E
  • Zigbee

Radiator thermostat

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 39 values from it, listed under Interface.

Connect it with

Specifications

The W600 is an electronic head for water-filled radiators. It replaces the manual thermostat on the valve, measures room temperature with a built-in sensor and drives the valve pin to hold a setpoint. Aqara sells it as models WT-A03E and WT-A03D, with Thread, Zigbee and Bluetooth radios in one unit. It runs on two AA alkaline cells, which Aqara estimates last up to two years based on eight months of heating use a year.12

Power
Battery. Two 1.5 V AA alkaline cells (3 V). Aqara estimates up to two years, based on eight months of typical use a year.2
Models
WT-A03E, WT-A03D1
Wireless
Zigbee or Thread, plus Bluetooth Low Energy1
Setpoint range
5 to 30 °C3
Setpoint step
0.5 °C on the dial2
Calibration offset
-5 to +5 °C1
Frost protection
Starts at or below 5 °C, stops above 8 °C; threshold adjustable from 5 to 15 °C in Zigbee mode1
Valve connection
M30 × 1.5 mm1
Adapters in the box
RA, RAV, RAVL, Caleffi, Giacomini, M28 × 1.51
Operating temperature
0 to 40 °C1
Operating humidity
0 to 95 % RH, non-condensing1
Operating noise
Below 30 dB2
Dimensions
⌀57 × 90 mm1
Display
LED, rotates 180° for vertical mounting2

Where it is used

  • Room-by-room heating setpoints in offices, clinics and serviced apartments with wet radiators, with the room temperature logged alongside.

    Indoor environmental monitoring

  • Checking which rooms call for heat outside occupied hours, using valve position beside the heating plant’s electricity or gas data.

    HVAC energy monitoring for commercial buildings

  • Holding frost protection in rooms that are closed for long periods, with an adjustable threshold of 5 to 15 °C.

Interface

Readings and settings, with units and ranges where Aqara publishes them. readable, readable and writable, writable only.

Download
ReadingUnitRange or valuesAccess
Measurements 10
Valve alarm - Binary state Read only
Window open - Binary state Read only
Climate - - Read only
Local temperature °C - Read only
Running state - idleheat Read only
Override active - Binary state Read only
Local temperature internal °C - Read only
Calibrated - not_readyreadyerrorin_progress Read only
Schedule upload status - idlestagedin_progresssuccessfailed Read only
Position % 0 to 100 % Read only
Controls 3
Occupied heating setpoint °C 5 to 30 °C Read and write
System mode - offheatauto Read and write
Preset - homeawaysleepvacationwind_down Read and write
Settings 25
Local temperature calibration °C -5 to 5 °C Read and write
Temperature setpoint hold duration min 0 to 65,535 min Read and write
Sensor - internalexternal Read and write
External temperature input °C -40 to 125 °C Read and write
Calibrate - start Write only
Temperature control abnormal notification - Binary state Read and write
Display flip - Binary state Read and write
Window detection - Binary state Read and write
Child lock - Binary state Read and write
Anti freeze temperature °C 5 to 15 °C Read and write
Preset home temperature °C 5 to 30 °C Read and write
Preset away temperature °C 5 to 30 °C Read and write
Preset sleep temperature °C 5 to 30 °C Read and write
Preset vacation temperature °C 5 to 30 °C Read and write
Preset wind down temperature °C 5 to 30 °C Read and write
Weekly schedule sunday - - Read and write
Weekly schedule monday - - Read and write
Weekly schedule tuesday - - Read and write
Weekly schedule wednesday - - Read and write
Weekly schedule thursday - - Read and write
Weekly schedule friday - - Read and write
Weekly schedule saturday - - Read and write
Save schedule - trigger Write only
Clear schedule - trigger Write only
Identify - identify Write only
Diagnostics 1
Battery % 0 to 100 % Read only

The valve opening is reported as position, 0 to 100 %. It is the most useful single point for seeing which rooms are calling for heat.3

Set sensor to external and write external_temperature_input (-40 to 125 °C) to control on a remote reading. Keep writing it while the mode is external.3

Open-window detection pauses heating for 30 minutes after a 3 °C drop within 5 minutes.1

Setup

  1. Switch it to Zigbee

    In the Aqara Home app, select the W600 and choose Zigbee as the connection method. The app loads the Zigbee firmware. A W600 that has been used before needs its button held for 10 seconds first.3

  2. Open pairing in Edge

    Open pairing on the Gateway’s Zigbee network in Edge, then hold the W600’s button for 10 seconds. It clears its network settings, enters pairing mode and flashes the pairing icon.1

  3. Fit it to the valve

    Pull the battery tab and fit the head within 5 minutes of power-up. Use the adapter that matches the valve, then tighten the M30 × 1.5 nut by hand.1

  4. Calibrate the valve

    When the screen shows F1, press the button three times. It shows F2 while it finds the valve travel, and after about 10 seconds it shows the set temperature.1

  5. Check one reading

    Confirm that Edge identifies it as Aqara WT-A03E, then change the setpoint from Edge and watch the position value move. Compare the room temperature with a reference thermometer and trim the calibration offset if needed.

Common questions

Does the W600 work over Zigbee out of the box?
Not always. It carries Thread and Zigbee, and the Aqara Home app has to select Zigbee before it joins a Zigbee network such as the Gateway’s. After that it pairs like any other Zigbee device.13
What is the difference between WT-A03E and WT-A03D?
Aqara lists both model numbers for the Radiator Thermostat W600 under one specification: the same radios, size, batteries, valve thread and adapters.1
Can it use a room sensor instead of its own?
Yes. Set the temperature source to external and write the room temperature to it from Edge. Aqara recommends an external sensor because the built-in one sits close to the radiator.13
How long do the batteries last?
Aqara estimates up to two years on two AA alkaline cells, based on eight months of typical use a year. Edge reports battery level so cells can be changed before the valve stops responding.2
How do I factory reset it?
Press the button twice, then hold it for more than 10 seconds. A 10-second hold on its own only clears the network settings and puts it back into pairing mode.1

Sources

  1. Radiator Thermostat W600 user manual (opens in a new tab) Aqara
  2. Aqara Radiator Thermostat W600 (opens in a new tab) Aqara
  3. Aqara WT-A03E device documentation (opens in a new tab) Zigbee2MQTT
  4. Aqara WT-A03E Zigbee definition (opens in a new tab) zigbee-herdsman-converters · v26.111.0

Further reading

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