Installing a Vaillant aroTHERM Plus 12kw and connecting to openheatmonitor

Hardware Heatpump
1

Hi, relative newbie here. I’m having a Vaillant aroTHERM Plus 12kW ashp installed to replace an aging gas boiler and upgrading a vented DHW tank which has a solar coil connected to a Viessman solar thermal panel. The whole installation will be done by a contractor under the auspices of Heat Geek. The house is a 1960s detached 5 bedroom c. 220m2 property in S Wales.

I’d like the system to be connected to the openheatmonitor website to monitor COP especially. We’ve been given a guaranteed COP of 3.9 and it would be good to monitor sysyem performance independently.

Can anyone tell me what I need to do this? Am I right to think that data can be taken direct off the aroTHERM heat pump? And is it best to have any monitoring equipment installed by the contractor or can this be done easily afterwards? They’ve given me a quote for connection to openheatmonitor of c. £800.

I’m relatively IT literate and handy with a soldering iron.

Thanks in advance for any advice!

2

Hi,
Welcome to the group.

I have a very similar install with a 12kW Valliant through a Heat Geek instal and a Heat Geek “mini store”. It is in a 1929 concrete block built bungalow with “extensions”, so no survey was going to get it right and I was keen to monitor as it went on. The only change I would now make is to ask for the new 11kW Valliant as it is half the size and not as ugly as mine!

I tried the Valliant app and found it less than satisfactory for anything timely and accurate. The full emon solution was what I would have preferred, but the install cost was too much for me so I tried the cheap and cheerful option. The big difference is that if you buy the full version you get support. The C&C option you are pretty much on your own and there is a bit of work to do.

The option I used was the ebus monitor option from Welcome to eBUS Adapter Shield - eBUS Adapter Shield C6
It took about a week to arrive from China

The instructions on the website are accurate but read them carefully. I skipped something the first time, but it was working again soon with a factory reset. It is pretty much like most esp32 devices.

If you are going to back it onto a raspberry pi don’t forget the “Pins” page and set then correctly. I didn’t spot that at first and went down a long rabbit hole…

I used the micro-ebusd option so you just need the device connected to wi-fi and then I used MQTT in Home assistant to present the data I wanted to see. You get a months trial to see if it works for you. As a home assistant and mqtt user it all come in very easily.

The key part for me was forcing the data to refresh as required, rather than when Vaillant decide it should be sent. You have the option to send every x no of seconds set on the software or you can force a data refresh through a home assistant automation.

So, you would want to be happy using Home Assistant to gather the data.

You can then just feed that direct into emoncms and onto heatpumpmonitor .or.
This video from “speak to the geek” explains most everything (but the variables are Daikin, not Valliant.

Connecting to the ebus is very simple. They are labelled on the Vaillant devices and you just piggy-back onto the existing ones.

Mine is powered by USB and it works reliably.

It can be found here HeatpumpMonitor.org

All the best…