Devices¶

The plugin creates its devices in 14 groups. Each device has a fixed unit number that never changes, so scripts and dashboards that refer to a unit keep working across updates.

Device names below are the English names. With another language, the names follow that language; a name you changed yourself is always kept.

Overview¶

Two labels are used in the tables:

• Gated: the device only updates while the compressor runs steadily, so idle and start-up readings do not end up in your graphs. See Gated devices.
• Unused: the device is created but not shown until you enable it. See Enabling unused devices.

Status¶

Controls¶

These devices change settings on the heat pump. Each write is checked against a fixed list of allowed settings; see Security.

Power input¶

Electricity used by the heat pump, as kWh meters that also show the current power. With Pump power compensation on, the estimated pump power is included.

Power total also counts every other mode (cooling, defrost, standby), so it is usually more than heating and DHW added together.

Heat output¶

Heat delivered, as kWh meters that also show the current heat output.

Efficiency¶

COP: heat out divided by power in. All three are gated, and each only updates in its own mode. See COP accuracy for the Domoticz setting that keeps the averages right.

Heating circuit¶

Hot water¶

Environment¶

Source circuit¶

The ground loop or well that the heat pump takes its heat from.

Mixing circuits¶

Only useful if your installation has mixing circuits; all four start unused.

Compressor¶

Refrigerant circuit¶

Temperatures and pressures inside the refrigerant circuit, plus derived values that show how healthy the circuit is. The derived values are most useful as trends over weeks and months; a single reading says little.

Reading the diagnostics¶

Refrigerant lift is the temperature gap the compressor has to bridge, and the main driver of COP: the smaller the lift, the higher the COP. It rises with hotter supply water (hot water mode, a steeper heating curve) and with colder brine. A lift that creeps up over a season at the same outside temperature points at a colder source or a higher supply temperature than needed.

Condensing-supply ΔT can be positive or negative:

• Positive (low-temperature heating): the condenser has headroom. A value that keeps rising at similar conditions can point at fouling or too little water flow.
• Negative (hot water, high supply temperatures): normal; the heat comes mostly from cooling the very hot gas rather than from condensing.

Discharge headroom is how far the hot gas is from the temperature at which the controller stops the compressor. Shrinking headroom over time is a reason to have the heat pump checked before it starts tripping.

Compression ratio rising over months at similar conditions can point at a refrigerant circuit problem, such as a slow leak or a restriction.

Statistics¶

Hours divided by starts gives the average run length. Many short runs (frequent starts, short last cycles) wear the compressor faster than few long ones.

Run time per day, week and month¶

Units 180 to 185 show lifetime totals, which only ever rise. Units 186 to 192 read the same controller totals but are Domoticz counters, so Domoticz works out the periods itself:

• The card shows today's run time (or today's starts) and the lifetime total.
• The device log has bar charts per day, week, month and year, for example how long the hot water ran each day this month, or on which days the backup heater came on.

The run times are shown in minutes ("Today: 84 min"). On a Domoticz version that lets plugins set a counter's divider, the plugin creates them in hours instead ("Today: 1.4 h"). Either way the stored values are the same, so you can switch an existing device yourself: in Setup → Devices, edit the device and set Counter Divider to 60 and Unit to h for hours, or Counter Divider to 1 and Unit to min for minutes. The plugin sets the divider and unit only when it creates the device and never changes them afterwards.

The counters start at the controller's lifetime total, so the first day's history begins when the plugin first created them; earlier days are not filled in.

Diagnostics¶

Last fault shows the newest fault the controller has stored, also after it was cleared, and "No faults" when there is none. When the controller stores a new fault, the plugin also writes it to the log as an error and sends one notification through your Domoticz notification systems. A fault that was already there when the plugin first read the controller is not announced.

Gated devices¶

Gated devices only send a value while the compressor runs at or above the controller's minimum target speed, once it has done so for 2 minutes in a row. During idle, start-up and ramp-up they keep their last value instead of logging misleading readings.

• Heating ΔT (63) and Source ΔT (102) also update during passive cooling, when the pumps run without the compressor and the temperature difference is still meaningful.
• Freq headroom (145) is not settled: it updates as soon as the compressor runs.
• The COP devices have further conditions; see COP accuracy.

Health bars¶

On Domoticz 2026.4 and newer, some cards show a coloured bar (under the title in the standard theme, along the top edge of the card in Machinon): green is normal, amber is worth a look, red is outside a limit. The bar's position shows where the current value sits. A device only gets a bar when its limits come from the controller itself, the WZSV or Luxtronik manual, or Alpha Innotec; there are no guessed limits.

What happens:

• The plugin writes the bars at start-up, and again when a controller limit changes, for example when the installer changes T-HG max. It does not rewrite them on every update.
• Your own bars are kept. If you change or remove a bar in the device's edit dialog, the plugin leaves that device's bar alone from then on. A device that already had a bar of yours before this version is not touched either.
• On Domoticz before 2026.4 nothing changes: those versions cannot store a bar set by a plugin.

There are deliberately no bars on the return temperature (during hot water it always runs far above the heating return limit), the brine temperatures (Domoticz draws an axis that crosses 0 °C from its centre, which makes the bar unreadable) and the source flow (the flow sensor reads below the manual's minimum in normal operation).

Enabling unused devices¶

Devices marked unused are created but hidden, to keep the dashboard tidy. To enable one:

1. Go to Setup → Devices.
2. Filter on the plugin's hardware name and show unused devices.
3. Click the green arrow next to the device and give it a name; it then appears on the dashboard tabs.

The plugin never switches a device back to unused, and an enabled device keeps its history.

Reserved unit numbers¶

Each group has room for new devices, so a future version can add a device without moving existing ones:

2-9, 17-29, 33-39, 43-49, 53-59, 68-79, 81-89, 94-99, 107-119, 122-129, 132-139, 146-159, 175-179, 186-199, 206-209.

Units 168-170 belonged to devices retired in version 2.1.0 and are not reused.