Circulation pump & circulation line not installed

Thank you for your assessment. We advertised and awarded the contract under VOB. The effort would have been very small during the rough installation phase. Retrofitting now is enormous...

What can of course be criticized is that you did not notice/complain about the defect early enough. You are obliged to minimize the damage. In this respect, the situation differs from my electrician case.

As a layman, I certainly wouldn't have been able to notice that early. It was listed in the allowances the whole time. If anything, it's a problem of the architect as site manager. To be honest, I don't feel like sorting it out on the way. Therefore, I hope it is still mainly the craftsman's problem. I have now made an appointment with a lawyer specializing in construction law. I think after that I should be wiser about what I can ultimately do and where I might possibly stumble over my own feet.

We received information from the installer today. He says the circulation pump contradicts the [BAFA funding] we receive for the drilling and the geothermal heat pump, as it worsens the annual performance factor. I am already aware that it worsens the annual performance factor due to the electricity required for the circulation pump. But is it true that you would not receive funding for a circulation pump?

Is that relevant? If the pump was agreed upon, he has to install it or reject it from the start before accepting the order. In my opinion, this is a cheap attempt to divert from the defect.

Yes, of course, that is not an acceptable answer. The question was rather, out of personal interest, whether a circulation pump actually means that we have no entitlement to funding for the Bafa subsidy for the ground source heat pump.