[APP][Pro] Atag Ariston Boiler

Apps
1

Hi all,

I have an Atag Lydos Hybrid heat pump water heater and wanted to control it from
Homey — mainly to heat it when my solar panels are producing. There was no app for
it, so I built one. It works on my own unit and I’d like a few more people to try it
before I submit it for certification.

Test version: Atag Lydos | Homey
Source: GitHub - WNijhof/homey-atag-lydos: Unofficial Homey app for the Atag Lydos Hybrid heat pump water heater (Ariston NET cloud) · GitHub

What it does

  • Set the target water temperature
  • Switch between i-Memory, Green, Program and Boost
  • Turn the water heater on and off
  • Read the current water temperature, whether it is heating, and the number of
    available showers — the temperature and shower count go into Insights

Flow cards: set temperature / set mode / turn on-off, conditions for mode and
heating state, and the standard temperature triggers.

Requirements

  • Homey Pro (2019 or 2023) or Homey Self-Hosted Server. Test version cannot be
    installed on Homey Cloud with a Bridge.
  • The water heater connected over Wi-Fi and working in the Atag app.
  • Your log in with the same e-mail address and password you use there.

Atag is part of the Ariston group and the Lydos Hybrid uses the Ariston NET cloud,
so this may well work for the Ariston Lydos Hybrid too — I just have no way to
test that. If you own one, I’d love to hear whether it pairs.

Worth knowing

In i-Memory the water heater learns your usage and starts adjusting the
temperature by itself from the second week on, so a setpoint you send from homey can
be overwritten later. If you want Homey to be in charge — solar surplus, dynamic
tariffs — use Green. That runs the heat pump only, up to 53 °C, and does exactly
what you ask.

Status is polled from the cloud every 5 minutes by default (adjustable per device,
2–60). Don’t set it too low: Ariston will rate-limit your account.

What I’d like to hear

This is tested on exactly one water heater, so the interesting question is whether
yours looks the same to the app.

  1. Does it pair? The app recognises the Lydos Hybrid by sys=4 and wheType=2.
    If yours doesn’t show up in the list, that filter is probably too narrow
  2. If pairing fails, please post the line Found n Velis plant(s): [...] from the
    app log (Settings → Apps → Atag Lydos → The gear → Make report). That single line
    tells me exactly what your device reports.
  3. Does the shower count match the Atag app?

Issues and pull requests are welcome on GitHub, but replying here is fine too.

This is an unofficial app, not affiliated with Atag or Ariston. The cloud API it uses
is not publicly documented, so they could change it without notice. Endpoints are
based on the reverse-engineered python-ariston-api project, which also powers the
Home Assistant integration.

2

This is not true, official apps can run just fine on Homey Cloud, even as test versions.

The reason that your app doesn’t run on Homey Cloud, is because only official apps (= developed by the manufacturer, or another developer in collaboration with the manufacturer) are supported there.