ᐅ Is a buffer tank useful for a heat pump?

Rübe1 schrieb:

Maybe I missed it, but is it really mandatory to repair it?

The compressor is broken and therefore there is no heating system (at most an electric heating element).

jens.knoedel schrieb:
The compressor is broken and therefore there is no heating (at most an electric heating element).

The electric heating element works only moderately. The hot water temperature is 32°C (90°F).

That electric heating element is supposed to keep the system running at least, is there something else wrong?

Anyway, replacing it takes two people about 1.5 days if they know what they’re doing. It also depends on the region you’re in and how particular the plumbers are at the moment.

In your case, I would choose a different setup: a heat pump as a standalone unit, with a 280-liter (74 gallons) domestic hot water tank, and that’s it. In a single-family home, you usually have enough flow rate, so you typically don’t need to worry about that.

Cost-wise: I replaced an air source heat pump about six months ago, the costs are similar. It was all-in, 18,000 including tax. Whether you can manage with a 4 kW pump needs to be calculated precisely, since that one is quite a bit cheaper.

Hmm, on closer inspection, one could conclude that a new heat pump increases efficiency, and then you’re dealing with the KfW, which suddenly makes it more interesting... there is a fact sheet on heating subsidies for private individuals – residential buildings.

jx7 schrieb:

Seasonal performance factor: 4.6

Rübe1 schrieb:

Hmm, on closer inspection, one might conclude that a new heat pump increases efficiency,

Phew, that’s going to be difficult...
I don’t see how that could be seriously justified.

Rübe1 schrieb:

Whether a 4kW heat pump will be sufficient needs to be calculated precisely; they are considerably cheaper, after all.

For the area, 4kW heating capacity is definitely not enough. He himself mentions a heating demand of 7-8kW.

Otherwise, I think it’s reasonable to adjust the control system during transitional seasons and to turn off the heating for a few days during a sudden spring warm spell like this week. With daytime temperatures of 13-15°C (55-59°F) and significant solar gains, the heating demand is so low that every heat pump cycles frequently.