An electric towel dryer with a display, sold by Atlantic. Its display names the model "ADELIS 2 DIGIT". It speaks io-homecontrol two-way like the Atlantic AGILIA IO radiator, so the hub sets its temperature, mode, boost and drying, and reads back all of them with the room temperature and whether it heats. Two units are reported on an SX1276 board (issue #202); see Heating and climate for the options.

Declaring it as a towel dryer

The towel dryer reports the same device type and subtype as the AGILIA radiator, an electrical heater with an adjustable setpoint (0x34/1). The radio does not say which of the two a device is, so its climate: entry adds io_model: towel_dryer. Without it the hub drives the towel dryer as a radiator: the target and the room temperature still work, but the mode writes go to the radiator's register, boost and drying are missing, and a Window sensor and an Open Window Detection switch appear that do nothing.

The block that Discover & Pair or Scan Paired Devices prints names the type and subtype only, so add the io_model: line yourself.

What works

Capability	Status
Discover & Pair	✅ Reported on two units; each has a key of its own
Target temperature	✅ Reported working from the climate entity
Room temperature	✅ Read on both units
Mode read-back (off / MANUEL / PROG)	✅ Read on the display's three modes
Boost and drying read-back	✅ Read during a boost and during a drying run
Heating / idle	✅ Read: the element's working rate is 100 % in boost and drying
Changing the mode from Home Assistant	✅ The display follows off, MANUEL and PROG at once
Starting or ending boost and drying from Home Assistant	✅ The display starts and ends both
Boost started on the dryer itself	✅ Shows as the boost preset and heating at the next poll
Comfort or eco period of PROG	⚠️ Experimental: read on one unit, in a comfort period and in an eco period; no second unit has confirmed it yet

Modes and presets in Home Assistant

Towel dryer display	Home Assistant
Off	off
MANUEL — holds the set temperature	heat
PROG — follows the dryer's weekly program	auto, with the comfort or eco preset of the period that runs (experimental)
BOOST	the boost preset, on top of the mode
Drying	the custom Drying preset, on top of the mode

Boost and drying run for the duration set on the display, and the mode underneath stays as it was. Select the none preset to end a boost or a drying run from Home Assistant.

While PROG runs with no boost or drying on top, the card shows the period the program is in: the comfort or eco preset, and the temperature the dryer heats to right now as the target. The hub reads the dryer's temperature in force at each poll and compares it with the comfort setpoint (comfort) and with the comfort setpoint minus the eco setback (eco). A temperature that fits neither, such as a frost-protection value, shows as the target with no comfort or eco preset. The comfort and eco presets are shown only: selecting one sends nothing and the hub logs a warning.

Note: Comfort and eco are experimental. They were read on one unit, in one comfort period and one eco period (issue #202). If you run a dryer in PROG, please report whether the card follows the display.

Working YAML

climate:
  - platform: home_io_control
    name: "Bathroom towel dryer"
    io_device_id: "BD684B"
    io_device_type: "electrical_heater"
    io_subtype: 1
    io_model: towel_dryer
    system_key: !secret towel_dryer_key

Give every towel dryer its own entry with its own system_key:.

Pairing a towel dryer

The menu path is the AGILIA radiator's: on the towel dryer, open Paramètres → Connectivité → Connexion, then press Discover & Pair on the hub. Follow Pairing a radiator for the key and the printed block, and add io_model: towel_dryer to the block before you flash.

Checking the declaration

At the first poll the hub reads the heater's model name and logs it once:

Device BD684B reports model name "ADELIS 2 DIGIT"

It also logs a warning when the declaration does not fit what the heater answers: a heater declared io_model: towel_dryer that holds no towel-dryer mode looks like a radiator, and a heater declared without a model that holds one looks like a towel dryer. The warning never changes what the hub does. An AGILIA radiator has not been read for these registers yet, so the wording stays "looks like".

Known quirks

No window function. The towel dryer has no open-window detection, so a towel dryer entry gets no Window sensor and no Open Window Detection switch.
The regulator reads "none" during boost and drying. The card's heating / idle comes from the element's working rate instead, which reads 100 % in both.
The remaining boost or drying time is not shown. The dryer reports it in minutes (rounded up), but no entity exposes it yet.
Changes made on the dryer show up at the next poll. The hub reads the dryer every five minutes by default, so a boost started on the dryer can take that long to appear in Home Assistant. Set status_poll_interval on the entry to read it more often.
The target in an eco period is the eco temperature. Setting a target from Home Assistant in auto writes the comfort setpoint, so the card keeps showing the eco temperature until the dryer returns to a comfort period, where it shows the new setpoint.
A change of the eco setback on the dryer shows at the next poll that the temperature fits neither period. The hub reads the setback at the first poll and again when the temperature in force fits neither period.
The weekly program is edited on the dryer. PROG runs the program stored on the dryer, and Home Assistant cannot change it. To schedule from Home Assistant instead, use heat and change the target or the mode from an automation.
A distant unit misses replies. One of the two units, received at about -90 dBm, answered three of six roll-call attempts; the near one, at about -35 dBm, answered every attempt.

Evidence

Corpus captures from issue #202, on an SX1276 board: