ᐅ Is a buffer tank useful for a heat pump?

Rübe1 schrieb:

And regarding better energy efficiency: I don’t need to be a great clairvoyant to know that if I install a modern pump with current technology, it will be more efficient than a 7-year-old unit.

You won’t notice any real difference. Especially not with brine-to-water heat pumps. A seasonal performance factor of 4.6 is effective, but just because today’s devices have more colorful screens for settings, there’s no major change inside the unit. In fact, the switch from harmful CFCs to “better” refrigerants actually reduces the efficiency of the devices.

Rübe1 schrieb:

If the new one is also properly sized (starting at 1 kW instead of 3 kW), then I will definitely be more efficient.

That’s true, a better-sized heat pump runs more efficiently. Unfortunately, that’s not enough for KfW funding / government subsidies. It would be nice—then I could replace my units every 10 years with new (better?) models and still claim 30-40% funding. Because these subsidies are likely to continue for a long time.

I have received an initial quote for the installation of a new heat pump: €36,000 (approx. $38,500).

jens.knoedel schrieb:

Even though the initial investment is higher. Heat pumps of that size should cost between €6,000 and €9,000 for materials plus installation (but more than disassembling, storing, repositioning, and screwing in again is not necessary).

That's right, but 36 is really outrageous. I'll take a German manufacturer as an example; their inverter unit has a list price(!) of 15,000. It ranges from 1 to 6 kW, plus some small additional items like MAG tanks, etc. So my estimate of 18,000 wasn't that far off.

Rübe1 schrieb:

That's right, but 36 is really outrageous. I'll take a German manufacturer as an example: an inverter unit has a list price(!) of 15. It ranges from 1 to 6 kW, and then you add a bit of small equipment like MAG and so on. So my price of 18 wasn’t that bad after all.

A Viessmann Vitocal 200 G 201.B08 was quoted for €16,600 (approx. $18,000). This heat pump can be found online for €9,500 (approx. $10,300).

The quote also included 104 labor hours valued at €9,000 (approx. $9,800).

An optional passive cooling system was offered for an additional €6,300 (approx. $6,900).

So, if I’ve read the datasheet correctly: R 410a refrigerant, F-gases—that’s where the next risk lies. Heat pump from the clearance rack, which is why it’s so cheap online, nobody wants it anymore. No inverter, so you’re jumping out of the frying pan into the fire. 104 hours. So two people are supposed to work on this for over a week? Oh man, I must be doing something wrong...

jx7 schrieb:

An offer was made for a Viessmann Vitocal 200 G 201.B08 priced at €16,600. The same heat pump can be purchased online for €9,500.

Additionally, the offer included 104 hours of labor valued at €9,000.

An optional passive cooling feature was offered for an extra €6,300.

This is a typical example of a defensive quote. It’s understandable that a tradesperson wants to earn money, but needing two people 1.5 weeks just to replace (!!!) a heat pump—and not a complete heating system installation—is quite bold. I seriously wonder what exactly they are doing during that time.