ᐅ Ice formation on brine line of heat pump

Created on: 29 Sep 2020 10:28
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Stadtvilla19
We have been using our Viessmann heat pump for a few weeks now. So far, it only needed to provide cooling and hot water, but now that the nights and days are getting colder, we noticed that the ground loop pipe has developed a thick layer of ice, especially in areas where there is little or no insulation on the pipe. During the day, the ice melts and drips, making the floor wet.

I thought this was due to insufficient insulation, and that fully and properly insulating the pipes should solve the problem. However, I recently read that while insulation may help prevent icing, it doesn’t address the root cause, and that this kind of ice buildup isn’t normal. Does anyone have experience with this?
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neo-sciliar
30 Sep 2020 10:23
guckuck2 schrieb:

The runtimes and cycles will only be a symptom. The problem is related to the heat source.

Actually, it's more the other way around. Extracting 320 kWh of heating capacity from the brine in one month is quite extreme. No new build in the world requires that much energy in September.
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Stadtvilla19
30 Sep 2020 10:53
What is ERRs? I’ll check later regarding the cooling and the supply and return flow. The next question is also who will cover the high electricity costs if the system is not running properly…
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neo-sciliar
30 Sep 2020 10:59
ERRs are single-room controls, meaning thermostats installed in individual rooms. Electricians like to install them (it’s a source of income for them), but heating engineers dislike them because they restrict the flow in the underfloor heating system.
The electricity costs are still manageable, but this needs to be sorted before winter, otherwise it will get cold eventually. Bring in the heating engineer. In the meantime, I’m happy to help where I can. (I now have 19 years of experience with brine-to-water heat pumps, but only with Waterkotte and Alpha Innotec.)
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Stadtvilla19
30 Sep 2020 11:09
No, we were advised against using those room thermostats because they apparently make a heat pump less efficient.

Our company apparently only installed Waterkotte systems back then, but then a new manager joined Waterkotte, and since then the service has reportedly worsened. Now, they have Viessmann as their partner. We had originally chosen the 333 G model with integrated cooling function. However, Viessmann now only offers the NC Box. Maybe this is where the problem lies, since the company doesn’t really know how to build a system with the NC Box... No idea...
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neo-sciliar
30 Sep 2020 11:13
Waterkotte has been sold to Nibe. Therefore, it is advisable to avoid Waterkotte for now, but NIBE is said to be reliable. We are currently planning the heating system for our new build. Viessmann is also being considered, but I am leaning against it. They have limited experience with heat pumps and should probably continue focusing on gas boilers.
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Heinz2k
30 Sep 2020 11:33
neo-sciliar schrieb:

More the other way around. Extracting 320 kWh heating power from the ground loop within one month is quite intense. No new building in the world requires that much energy in September.

Exactly, which is why the seasonal performance factor for heating still looks quite good under these conditions. Do they have a buffer tank installed? How high are the compressor starts (you can read that out)? What is the heating curve like?