7 posts were merged into an existing topic: eBUS hardware adapter (and ebusd software) Thread
I am not any sanitary expert, so take it with pinch of salt. Long answer short yes. If you have 55 in reservoir, it is much lower at the tap. Is there hot water circulation? What is the turnover? The bacteria are present in water in many households, the problem is when you breath it in. Do you shower? Do you have kids that play? The odds are super low, but not worth the risk. Too many variables. For me, it is not worth the few euro saved per year to risk anything.
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I’m in a similar situation, for me the main reason is that I have a number of unused taps (installed by the previous owner) that I cannot regularly flush. There has been some more rather “hacky” work around the plumbing here so to be safe I regularly do a legionella cycle and open the unused taps (around once a week, when it’s as warm outside as possible).
Good graphical explanation of how the “energy integral” works. This example uses -120 °min though. Arotherm Plus uses -60°min
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I currently only have hot water enabled and saw this behaviour tonight:
Target flow temperature was automatically set to 40°C, the compressor was on shortly to bring flow temperature to 20°C and the pump was switched on in short regular intervals to circulate the water.
Is that a frost protection cycle? Temperature was around 5.5 °C at the beginning, then dropped and was again around 5.5°C when the behaviour stopped.
Hi Guys,
I’ve moved a bunch of ebusd queries and replies from the past week or so over to the dedicated Arotherm ebusd thread.
Not everyone with an Arotherm has an ebus adapter and didn’t want this thread to become dominated with it. 
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Hi Daniel or anyone else who can help.
We’re at the stage of getting quotes for an ashp and an installer has quoted for a sensoCOMFORT which also seems to be called VRC720/3 from an online data sheet.
The options also list a VRC700 for a controller so I asked why their choice, and got the reply that it was easier to use.
I’ve no objections to easy to use but has anyone any experience of both?
I have to plough through the data sheet for the sensoCOMFORT but knowing whether the beautiful marketing language works in reality can only ever be a guess.
So if anyone knows please contribute your experience
Thanks very much
In my system the sensoCOMFORT is used in the living area and I supose could be considered to include a room thermostat although the heat pump is primarily weather compensation controlled.
I think the VRC700 is just a room thermostat that is wirelessly weather ompensatable but mor aimed at boilers.
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I also have the VRC720 but for me it’s sitting in the basement and my heat pump runs on pure weather control. It acts as a system controller but I have never had to use it after the initial setup as anything not on the installer level is done on the app instead. For that you need a sensoNET which acts as a Gateway between heat pump and smartphone.
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VRC700 is and older controller. VRC720 is the current/latest model.
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We obviously want weather compensation and a flag was set for me when the vrc700 had that in the title but the 720 didn’t
Since I’ve read the Vaillant system isn’t easy to get your head around then they must have improved the human interface in the more modern one.
Thanks guys!
It’s not too bad from a UX perspective. What I like about the controller is that you have a “?” button that you can press at any point in the menu to get an explanation what the setting does. You’ll have it figured out in no time and then notice you won’t even have to touch it that often anyways 
.
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Update: having spoken to the installer, who in turn spoke to Vaillant UK, this is apparently the frost protection on the DHW cylinder, which is hard-coded to kick-in at 12C. There’s no option to turn this off. It’s not mentioned in the manuals, but there’s a passing reference to it on the website (bottom of the page): Controls and frost protection | Vaillant
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Had a 12kW Arotherm Plus installed this last week. Noticed there are a few mentions of firmware differences earlier in this thread - just wondering if anyone is able to confirm what the latest firmware versions are?
I had a look on the VWZ AI module and it gave me two values:
01 - 0351.09.01
02 - 0360.03.01
Second query I set a Legionella cycle to run today to see what it would do and noticed some massive / impossibly large? spikes in flow rate once the flow temp exceeded 62C. Any thoughts on a) are these real? b) If real, is there an issue that needs resolving / worrying about? c) if it’s a quirk of the monitoring /reporting, again anything I need to do or worry about?
Did notice the water is super hot now - if I read it correctly it holds the diverter valve on DHW and the pump on for a period after the heating to ensure it remains hot. Looks like the water is at 70C. Kind of makes me worried about someone scalding themselves if used to a set temperature and then the cycle runs without them remembering …
Hi, welcome to the forum!
Which heat meter do you have? There may be some trapped air messing up the flow readings.
Its a Kamstrup QP6. Looking through my data first time its flowed past 60C, so I could still have some air to work out of the system. There is an automatic air vent on the flow pipe into the cylinder and another 2 at the highest point of the rad circuit, so hopefully this will just work itself out in time?
Does feel more intuitive to be a reading issue than a real reading given it reading a flow of almost 4 times the ability of the pump!
Our new post and article may be well timed Declan
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Thanks Mick - interesting article! Certainly seems odd that when they’re running a design that doesn’t (really) facilitate firmware upgrades that ‘new’ stock is shipping without the absolute latest firmware. But I suppose the boards are built when the boards are built and if they don’t even acknowledge 06.07 as faulty …