Cannot set quiet mode on an Altherma 3 R W

[Staacks]

Just installed to test the power limits in quite mode (as suggested in https://github.com/Arnold-n/P1P2MQTT/issues/69#issuecomment-2119007683), but I am not able to set the quiet mode / quiet level.

In HA I see Quiet_Level, Quiet_Level_When_On and Quiet_Mode. The latter do not reflect the actual setting of the heatpump and changing them has no effect. Quiet_Level actually changes correctly if I manually set the quiet level on the heatpump's control panel, but changing the entity does not have an effect and its value just resets to the old state.

Via telnet I can actually see that the HA entity results in an action on the P1P2bridge:

[MON] 2024-05-19 12:28:59 Initiating parameter write for packet-type 0x3A parameter nr 0x4D to value 0x1
[MON] 2024-05-19 12:28:59 Initiating parameter write for packet-type 0x3A parameter nr 0x4C to value 0x2
[MON] 2024-05-19 12:29:00 Executing E command for packet 0x3A setting param 0x4D to 0x1
[MON] 2024-05-19 12:29:00 Executing E command for packet 0x3A setting param 0x4C to 0x2

I am running an Altherma 3 R W heatpump (EHBX08EF9W) without any additional P1P2 devices (no wall panel, no thermostat, no LAN adapter etc.). (Arnold, you might remember that we were in touch via email in March.)

Also, there are a few things that surprised me about the quiet mode on my pump and I am not sure if that is normal or the reason that it is not working: I am not allowed to change the quiet mode on a user level (only with the installer code) and the quiet mode is not reflected by any field. Both are also documented in the manual (sorry, these are screenshots of the German manual, but hopefully it still illustrates what I mean).

The two asterisks mean "only accessible by the installer", so I am allowed to change the programming if in auto mode, but noch change the mode or level as a user.

This is the quiet mode level setting and the empty second column is where other settings have a field code associated with them.

Not sure if any of this is unusual or related with the problem.