Reading Vaillant Arotherm+ system pressure remotely

Hardware Heatpump
1

Hi. I noticed that in myVaillant app V2.x the system pressure was available but

cannot find it in versions 3.x. Maybe I missed it ?

It is also seems to be absent from the output of myPyllant.export, so suspect Vaillant

is not supporting it.

Short of physically going to the plant cupboard or using the VWZ-ai control or installing an ebus adapter anyone know of any way of reading system pressure remotely ?

Thanks,

Nick

2

Hi Nick,

for me, it’s right in the “Status” tab accessible in the bottom when you open the app. I’m on version 3.40.

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3

No pressure here in my 3.4 app.

I have it connected to vr 940f.

It’s a shame there isn’t more useful info in the app.

4

Hi Andre. Unfortunately mine only shows flow temperature, current power use, running time and on/off cycle count.

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I don’t have the hydraulic station, and the gateway is a VR940f whereas yours is a VR921.

I am also on app version 3.4.0.

Interesting you have the system pressure as well.

Cheers,

Nick

5

Same here,

Cheers,

Nick

6

It’s present for me with a 940f and app 3.4. Also shows in home assistant via mypyllant.

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7

That’s interesting Andy. I only have the one box below Operation mode / Heating

What’s your Arotherm Firmware version ?

Mine’s 404.1.28 .

I can read the system pressure on the VWZ-AI (white) controller under Live Monitor, so obviously it’s not a bad sensor or connection.

I don’t use HA, but judging from the myPyllant.export python command and the lack of a reading in the myVaillant app I suspect that’s not a solution either.

Thanks,

Nick

8

I think whether pressure displays or not is linked to the currently-set ‘System Diagram’ value; by default, this is set to ‘10’, which is meant for a system with a buffer/hydraulic separation. This will not report pressure, due to assumed hydraulic separation

Many installers don’t bother to change this value to ‘8’ (typical for an open-loop system without a buffer).

9

Yes mine’s on 10 since I have a 4 port buffer - I don’t think the post buffer pump will run if set to 8.

Not sure why having a buffer will affect system pressure as it’s all one closed body of fluid and hence all at the same static pressure.

As I said to Andy B, the system pressure is available on the (not conveniently placed) white VWZ-AI controller so definitely being read from the ebus.

Maybe I’ll ask Vaillant.

Thanks,

Nick

10

You will not see pressure being reported via the app/MyPyllant with ‘System Diagram’ set to 10, this is by design.

11

Mine is system diagram 8 and I have I no pressure on the app. Neither is it on home assistant, so it doesn’t seem to be openly broadcast. Which is odd as it’s on the sensotherm.

Would be nice to get more useful information on the app.

12

Thanks James.

I can’t see a pattern to this.

It is not in the information on my SensoComfort either. It only appears on the VWZ-AI

in the Live Monitor section.

I will ask Vaillant or my installer when they return from Xmas break to see if they can shed light.

Not life critical.

Nick

13

Just to confirm, I’m on configuration 8 and my firmware version is 404.1.28

14

Thanks for that Andy.

Nick