Compressor broken after 6 years (Ecoforest ground heat pump / well construction Heth)

That's why I said software, in the sense that the same thing can happen to you with a new combustion engine, since they are also completely software-controlled.

I have meanwhile received the statement from a craftsman that a heating capacity of 7kW to 8kW would have been ideal for our house and not 12 kW.

A neighbor with a similar house size and similar energy standard installed the same heat pump around the same time.

His values are as follows.

Hours: 28545
Starts: 10997
Starts/hour: 0.385

1) For them, the number "starts per hour" makes sense. It is exactly the quotient of the two numbers above.

2) It is noticeable that we have five times as many starts as they do. That is certainly the reason why the compressor broke down after six years and not after 30 years.

Now we just have to find out how to configure the heat pump so that this doesn't happen again in the future.

I still wonder how it could have happened that the installing company
a) sold a heat pump that was too large and
b) configured the heat pump incorrectly and also did not notice this during the maintenance that took place.

I can help you with that. Our heating system is exactly the same, also oversized and incorrectly parameterized. The most important thing is that all heating circuits are always fully open, maximum. No ERR active. Then lower the flow temperature as much as possible and bring the rooms to the desired temperature using the adjustment thingamajigs on the underfloor distributors. There are good instructions online.

You have to understand why it cycles. It does that whenever it cannot dissipate the output or needs a lot of power. Like in a car, actually. You can reach the destination steadily at a constant 80 km/h or go full throttle at 180 and then 30 km/h in alternation. Option 1 is better, usually also significantly more economical because it is closer to the ideal performance curve.

For me, it reduced compressor starts to at least one sixth and saved about 30% on heating costs.

2) It is noticeable that we have five times as many starts as they do. That is certainly the reason why the compressor broke down already after six years and not after 30 years.

Damn, that's how I expected and wrote it. Your compressor lasted really long. Solution see .

I still wonder how it was possible that the installing company a) sold a heat pump that was too large and b) configured the heat pump incorrectly and did not notice this even during the maintenance that took place.

Unfortunately, many companies simply have no idea. Whether due to lack of training, interest, or skill. They’d rather install an oversized heat pump than have the customer come back saying it doesn’t get warm. Whether the heat pump breaks down after a "short" time doesn't matter to them at first.

Hello JX7! I read your article about the defective heat pump with great interest. Was the local heating and climate technology company able to fix the heat pump for you? I could also urgently use some help. Our Ecoforest - about 7 years old - has been malfunctioning since the end of Oct. 2023... that's really bad. Can you tell me the company that hopefully was able to help you? That would be great. Many thanks in advance!