VBO PWM not available as sensor

[lukef82]

I would like to read the VBO pump PWM (to be able to estimate this pump power consumption), it relatively recently appeared in the web interface of the heatpump, but it is not in the home assistant integration (neither this one, nor the original one from Buoni). Would it be possible to add it, or provide me with a few pointers on how to read a new parameter from the data stream?

Thanks, Luca

[Kars-de-Jong]

The PWM signal for the VBO is calculations.ID_WEB_HZIO_PWM.
The PWM signal for the HUP is calculations.Circulation_Pump.

[lukef82]

That's great, thanks! I went through (at least I though I did) all the calculations, but I missed that!

[rhammen]

Both PWM signals are now implemented and merged (#778) — they will be in the next release.

🆕 What you get

Two new sensors on the heat pump device, disabled by default (enable them under Settings → Devices & Services → Luxtronik → the heat pump device → +n entities not shown):

Sensor	Register	What it is
Pump PWM	calc 183 ID_WEB_HZIO_PWM	the VBO / brine (heat source) pump — the one you asked for
Circulation pump PWM	calc 241 HUP_PWM	the HUP / heating circuit pump

Thanks @Kars-de-Jong for naming both registers — that is exactly where they live.

The value is passed through unscaled: the library types both registers as a percentage and the controller already sends one, so no conversion is applied. Neither sensor is gated on a visibility flag or a firmware version — both registers turned out to be present on every controller in our diagnostics corpus, from V1.73 through V3.92.3, so the integration simply checks whether the register exists.

🙏 One measurement would help

While checking the 29 diagnostics dumps we have, two units running V3.8x firmware reported calc 183 above 100 (390 and 708) where every other unit stays neatly within 0–100. That looks like those models may report per mille (39.0 % and 70.8 %) rather than percent, but a stored snapshot cannot prove it — the value is left unscaled for now rather than guessed at.

@lukef82, you have the number in the controller's web interface, which is what would settle it: while the pump is running at something other than 0 or 100, could you compare the VBO PWM percentage shown on the controller with the value of the new Pump PWM sensor in Home Assistant, at roughly the same moment? If the two agree, the scale is right as shipped. If your unit is one that reads high, we would want to know the firmware version too (it is on the Firmware version sensor, or in the controller's menu).

Anyone else reading this with a heat pump whose Pump PWM reads above 100: the same comparison from you is just as useful.

➕ Along the way

Reading the register maps closely for this turned up three unrelated defects that are fixed in the same PR — nine calculations were labelled with a register number they did not actually read (the Luxtronik_Key attribute showed the wrong index; the values were always correct), one visibility was defined twice, and the placeholder names the library generates for visibilities were using the wrong prefix. Nothing changes for existing entities, values or automations.

[lukef82]

I just checked:

You can see the webinterface, the new integration PWM signal and the signal (yellow) from the old integration which I manually added. they all match apart from a delay in the new integration.

I am on V3.92.2

Thanks for the work on this

Luca