Air-to-water heat pump without buffer storage | Heating installer refers to building energy law requirement

If I remember correctly, it came to me on the third day and that was a Saturday or Sunday (!).

...that’s really quick then.

Does anyone of you happen to have experience with writing for ERR exemption from the mentioned IB? Is it basically a done deal for the exemption, or are there still several official hurdles to overcome and especially, what timeframes are to be expected? If the ERR exemption went through, I would practically have settled the discourse on a factual basis with the heating technician. However, if no exemption were granted, my argumentative basis would become somewhat "thinner" again.

...and one more question: "Is the system ultimately actually accepted by an energy consultant with regard to Energy Saving Ordinance requirements?" I’ve never heard of that. Are there any experiences with this?

Thanks & regards

You are not the builder. You are the buyer.

True, sorry. The developer completely stays out of the topic of the buffer tank. He says I should coordinate it with the contracted heating company, as he doesn't care whether the heating system is set up with or without a buffer tank.

Is it then basically a slam dunk for the exemption, or are there still several official hurdles to overcome and above all, what time frames can be expected?

According to Heckmann, success rate is 90-95%. So almost a slam dunk, definitely worth a try.

"Will the system actually be approved in the end by an energy consultant regarding the Energy Saving Ordinance requirements"?

If he does his job properly, he looks at everything. And missing ERRs stand out. What could work are used ERRs stuck on from eBay that are not even connected. But your heating technician won’t go along with that. That’s cheating anyway...

because he doesn't care

He may casually tell you that verbally, but what is on the one hand recorded in the construction service descriptions as part of the (purchase) contract between you and the builder and on the other hand in the contractual relationship between the builder and the heating technician is binding in the first place.

basis for argumentation

You don't have that, as there is no contractual relationship with the heating technician.

Since we didn’t want to start a small war because of the ERRs, we agreed with the Heizi on "zones" in which similar temperatures should be controllable respectively. That means we have a total of three ERRs: one ERR for everything related to living (i.e., cooking, eating, office, children's room, etc.), one for bathrooms (= a bit warmer), and the third for sleeping (= a bit cooler).

In practice, we don’t really use the things (you really don’t need them), but I didn’t feel like having skirmishes with the bureaucrats. And those few E(eu)RR(o) were worth it to me ;)

About the buffer tank: At the time, BAFA actually required it for the heat pump subsidy. However, in the details, there was the option to credit the volume of the underfloor heating. This could also be ticked or even calculated in the craftsman's declaration. It’s a nice counter-question anyway: Why 30 liters of buffer tank when you have 200 liters of underfloor heating that lie in several tons of storage mass (= screed)? Completely absurd. Maybe that’s where it comes from? It’s unknown to me from the Energy Saving Ordinance, and I would definitely want to avoid the buffer. You can simply disconnect the ERR. At least insist on motorized valves that are power-fail safe, then you only have to remove the fuse. A few years ago, the general consensus was that exemption applications from the ERR were rather unpromising. But if that has changed … better to pay a few euros for the paperwork than for unnecessary, expensive, ugly ERR on the wall.