Hello Guys.
my Vaillant 55/6 was just installed yesterday, and I am struggling somewhat with the settings (from the VRC720). The installer was not very familiar with Vaillant , and he did just the basics.
The overview: Vaillant 55/6, no buffer, only heating, 1 zone, all K33 radiators, 35mm primary pipe;
with the circulating pump at Auto setting, I am getting 850 l/h, but it stays at this level ALL the time !?
Insider temp 23C / outside temp 4C now;
Now, this is where I would ask for your help:
Control/Zone1/Heating Mode: Manual OR Time contr. ? (I want constant internal temp, all the time)
Installation/Adaptive Heat Curve: Deactivate or Activated ? => HeatGeek was mentioning to keep this deactivated (maybe I misunderstood)
HP Control Module config: MO 2 Circ. pump OR M1: 1x circ. pump ?
Installation/Circuit 1/Heat Curve: is this used ? since above point 2 is deactivated ?
Setback Mode: Eco OR Normal ?
Room temp: Inactive, I assume, considering that I want full weather COmp.
Yes it does this, don’t worry. The Arotherm uses DT to modulate output
Time control
Deactivate. Not heard of anyone having any joy with this.
Not sure on this one.
Choose the heat curve to match your heat loss.
I wrote this article
Normal
I go with active (with room influence). Again, mentioned in the weather curve doc
So choose your setback temp, say 18C
Then in your timed programs, choose your target indoor temp, say 20C
04:00 - 22:00 - 20C
Then if you leave the rest of the day ‘blank’, setback at 18C will kick in and the heat pump will adjust the weather comp curve down to match.
With all the above settings, the only thing you’ll change is the heat curve.
If you’re too hot, turn the curve down.
If you’re too cold, turn the curve up.
Once you’ve changed the curve, give it a day to see how things settle.
This depends on your setup I think. I’m not a heating engineer, but we’ve just got this sorted after a very puzzling few weeks from installation, after the circulation pump turned out to be wired into the wrong output. (One of those “very simple in hindsight, but incredibly hard to diagnose with the information available” things.) I thought it worth posting just in case anyone else hit the same issue.
As far as I understand it, one’s system might have:
1. Only the pump inside the heat pump unit, in which case MO 2 / M1 is probably irrelevant. From your description of your system, this sounds like your situation, and I think you can probably set these both to “not connected”. 2. A secondary circulation pump for the heating. We have one installed post-buffer tank, which is wired into output MA1, and the HP control module config is set to “MO 2: Not connected” & “MI: 1 x circulation”. It (now!) comes on when the heating is on, and works in tandem with our two zone valves. 3. An optional secondary circulation pump for DHW, wired into output MA2. This is for those who want “instant” hot water badly enough to install a return loop in their hot water piping, and they can then use the DHW circulation pump schedule to control when it circulates.
Our problem was that the heating circulation pump was wired into MA2, and was being controlled by the default settings in the DHW schedule. So our system effectively responded perfectly during the day, and ignored all inputs at nighttime, because the pump was switching off, and at night the HP was merrily topping up the buffer tank instead of the house! Bamboozled us, our (otherwise very competent) installer, and Vaillant, as the symptoms were sending us chasing after app and control unit firmware red herrings. I allowed myself a smug/wry smile when I managed at last to diagnose it
I’m curious to know other Arotherm owner’s experience of defrost cycles and the effect on COP in recent days. I’ve been watching my stats and my COP really takes a beating during the defrost itself (obviously), but also during normal operation between defrost cycles as it gradually ices up and efficiency drops. I’m seeing defrosts about every 45 minutes at current RH levels (sorry don’t have an outside humidity sensor to give a value on it). My flow temps are very modest, currently between 28-32C, so this seemed like quite a frequent defrost regime to me.
My other observation is that during DHW runs, there is no defrost cycle. Is this intentional by Vaillant to just to hell with efficiency, let it frost up but just get the DHW cycle completed. My DHW run last night was 3 hours long at significantly higher flow temp than heating (obviously) and was not interrupted by a defrost cycle.
Cheers,
Tom
Interesting. What kind of cylinder have you got? That’s not a DHW profile I’ve seen before, running at maximum temperature instead of ramping up like Mick’s perfect example.
On ours, yes the noise ramps up. I noticed a buzzing that on closer inspection is just the case (maybe a screw or something), as it went away when I pressed on it
Our ecodan took 90 minutes for a 170L DHW cycle at -1°c here last night. I wish its controller was a bit smarter at waiting in terrible but improving late evening weather.
For those of you that use/monitor “Working Figure” on your Arotherm installs. The heatpump controller DOES know about month boundaries. It must get it from the sensocomfort?
You can see here where I’ve recorded monthly heating working figure via the ebus in to
Home Assistant. It flips instantly on midnight into the new month and starts a new calculation.
I assumed the controller was a bit dumb and did a rolling 30 days or something. But the evidence suggests otherwise.
So bear that in mind when looking at ‘month’ working figures.
Yes, can be. Mine starts off quiet, then as it ramps up it goes through a noisey spoy. Then when it gets closer to maximum speed it quietens down though can still here a slight hum. Then get the same going back the way as it cyclez off. I’ve got a 7kW Arotherm Plus. Has the reciprocating compressor. Would be interested to hear from those with the 12kW with the scroll compressor. From my time working with HVAC scrolls are quite quiet.
Hi there, new but have a few questions about my arotherm plus 7kW. I had it installed in October 2021, replacing horrible storage heaters. Generally I’m very happy with it. However Im wondering if its working as it should
I don’t use time control for the hearing. Purely on setback which is 19°C, SensoComfort control is mounted in the vestibule of my house where the balance radiator is (no thermostatic control on it)
Heat Curve is set at 1.2, I have not messed around with any settings. Just viewed them.
Typically, my unit will display actual temperature 19°C, matching the desired temperature. Then every couple of hours the heat pump will cycle on, even though measured temperature has not dropped (I’m understanding there is some algorithm from reading the manual) In milder temperatures it might come on for 10 minutes then cycle off. However in the cold weather I’ve had I’ve noticed some odd behaviour.
The heat pump will cycle on, ramp up to maximum capacity, stay on for however long it needs to hit the target flow temperature. All good. The I hear and also see on my smart meter that it is ramping back down, usually it goes off. In this case though i then see it start to come back up and continue longer. This perplexes me as it has met target flow tempersture. My desired temperature on the controller matches displayed temperature.
I have a weather compensation unit on my house too.
Also, should the compressor always go to maximum capacity? Reading the technical data it has a variable speed drive so should modulate how much power it needs. The only times that it seems to run at less than full capacity in heating mode is if outside air temperature is greater than 14°C, anything below that and it ramps up to full.
Apologies for the brain dump. I used to work designing and building HVAC units so familiar with compressors, heat cycme etc, but they were simple systems. Any insight appreciated.
1.2 was suggested by Vaillant, my system was fitted under the Warmworks Scotland schemrle. I cant remember seeing the heat loss calcs but i have all the documentation somewhere. Will look it out.
I have a 7 kW aroTHERM + ASHP with a sensoCOMFORT 720f controller. Can anyone point me to an explanation of the parameters listed in the Installation Configuration setting. What they do and what setting to use would be most welcome. I’ve gone there to change the heat curve, but that’s about it.
Also I’ve noticed that the sensoCOMFORT room temperature seems to read ‘high’. I’ve got a couple of other room thermometers (different brands) which agree closely and typically yield temperatures between 0.5 and 1 degree less than the sensoCOMFORT. Same with the radiator water temperature, only here the difference is more like 3 degrees?
I found the installion manuals and the installer write in 56 deg Supply, 48 degrees return. Now im assuming he was told by the designer to set it up as that. I don’t have the design report, but i have the survey paperwork the surveyor did, room sizes, insulation, wall thickness etc. I’ve turned m heat curve down to 1.00.
If i upload photos of what I have can anyone assist. Like it works, house is warm. I don’t think it’s faulty. Trouble is I’m an electrical engineer, with an engineers curiosity, with heat pumps i have enough knowledge to be dangerously if that makes sense.
, and he did just the basics.
if that makes sense.