Vaillant have announced updates to the Arotherm Plus, as well as new models: Arotherm Pro and Perform.
From the press release, looks like Vaillant are doing away with eBus and moving to a new comms protocol, as well as simplifying the ancillary hardware; instead of needing the VWZ AI controller + SensoComfort + myVaillant Connect + optional VR71 wiring centre, there is now just a single ‘iQconnect’ integrated controller with wifi and over-the-air updates.
There are also claims that the new models are ‘quieter’ and ‘more efficient’… I wonder if the complaints of noisy buzzing compressors had an effect!
Any idea when the updated models will roll out in UK? I’m still tempted to try to use my HeatGeek performance promise to get my 5 replaced with a 7, but only if they’ve sorted the noise of the 7s…
Setpoint: 46.0 °C
Target flow temperature: 0 °C
Cylinder charging hysteresis: 5.0 K
Cylinder charging offset: 2 K
Should the flow temp be rising so high when doing the DHW cycle?
My installer commented on it when doing an annual service. Had not bothered me personally, with respect of cost/performance, but they felt the hysteresis setting might not be working as designed. It was on 10K, they reset so we could compare the result.
The hysteresis setting and the flow temperature arent linked sofaik.
The hysteresis determines the temperature to which the DHW must fall before it reheats. DHW reheat is initiated when (DHW is programmed to ON) AND (actual DHW temp < set temperature-hysteresis)
The flow temperature is determined by the DHW target temperature and the Vaillant control system, which evidently adjusts the flow to achieve the set temperature. The exact algotithm isnt disclosed but from the plots (I get something similar) it looks as though its based on measuring the DHW temperature and the return temperature. The uplift ultimately required from set temperature to flow temperature will be determined principally by the coil area in the tank, larger coil area = smaller uplift. The DHW ECO setting might also affect this figure, obviously its possible to reheat more slowly/more quickly by adjusting the offset and the ECO setting may well change this.
I believe that the ‘offset’ is yet another parameter basically to correct for any error in the temperature sensor measurement of the DHW temperature.
Does anyone now the expected resistance at various temperatures of the DHW temperature sensor. My machine intermittently displays a sensor error and also intermittently fails to display the DHW temperature. Ive checked the extension cable and its fine, the sensor itself measures about 2.5K
On a separate more general issue, is there a way to display latest posts in any given thread first, as opposed to earliest posts (which is what happens to me). The latter is more useful as you dont have to scroll through everything.
I don’t know about per thread, though you could try searching for “Discourse show latest post first”.
The easiest way to see all latest posts is with the shortcut keys [ g ] [ l ] (get latest), which will give you a red line when you last visited, everything above is new (to you) or pinned.
The scroll bar is a quick way to move about in a long thread.
Probably a red herring, but are you logging on first? If you do, you should get the “last visit” red line at the top of the screen and only the newer (unread) posts below it. If you don’t, you’ll be taken to the top of the thread.
I don’t understand your point - the cursor can be anywhere. It’s your fingers that you put on the keyboard and type the letters gl in that order. It’s clearly not useful to you as you’ve now added that the View Latest button doesn’t do as you require, and it’s equivalent to clicking that.
Looking at the Discourse forum about Discourse, I think there might be no facility to do as you request – that’s my impression, but I could be wrong.
Hi everyone,
I’ve been having an issue with the hot water tank temperature sensor — it shows a temperature that’s about 15°C lower** than the integrated temperature gauge on the tank.
I replaced the temperature sensor with a new one, but the difference is still almost 15°C.
Also the correct temperature is one on the integrated gauge.
Where are the two sensors on the tank? Is the one that reads lower physically lower? If so then you may have stratification, which can be a good or a bad thing.
Hey, yeah, integrated gauge on my tank is on upper half but other sensor goes into the hole and is 15-20 cm lower, and temperature reading on my vrc700 is from that other sensor.
When everything was installed 2 years ago, temperatures were almost the same and everything was working normally
I tried emptying hot water tank, gauge was at 22 C and sensor was showing 19 C. Then I set temperature to 48 C, after heat pump heated water tank sensor showed 49 C and gauge on tank was showing 54C, I again set new temp to 60C. sensor showed 61C and gauge was showing 64 C.
After that in the evening 5 min shower, evening routines and now morning routines where hot water was minimally used, sensor shows 24C and gauge 54C. My how water tank is 200 L, is this normal, i cant tell anymore O.o
Sounds normal to me. My lower/center sensor is also extremely sensitive to cold water inflow. Have a look at this thread: Altherma dhw temperature suddenly drop. Here’s the screenshot from my answer there comparing top and center sensor for my 300l tank:
