ᐅ KfW55: Gas or Air-to-Water Heat Pump with or without Photovoltaic System

Created on: 26 May 2016 10:07
B
bvlgari
Hello,

I’m overwhelmed by all the acronyms in the subject line. I asked a similar question elsewhere, but it seems I wasn’t in the right place, as I didn’t receive good answers.

We plan to build in NRW (Dortmund) and have not yet decided on the heating technology (single-family house, 150sqm (1615 sq ft), solid construction, underfloor heating). According to KfW55 standards, these two options are suitable for us:

  • Condensing boiler, solar domestic hot water system (standard values according to DIN V 4701-10), centralized ventilation system with heat recovery (heat delivery rate > 80%)
  • Air-to-water heat pump with surface heating system for heat distribution, centralized ventilation system with heat recovery (heat delivery rate > 80%)
Initial costs: Option 1 is cheaper, even though with Option 2 we can avoid a gas connection.
Operating costs: can we consider them about the same?

Options 1 and 2: I have to drill holes in the wall to get fresh air for both options. When is it necessary to have an unsightly box (fan) placed outside the house?

Option 2: We were recommended the THZ304 (integrated system). Is this suitable for our house and average consumption? There is also a THZ304 SOL version of the system.

Option 2: Would it be worthwhile to install photovoltaic panels as well, to avoid high electricity costs during the cold months (for the electric heating element)? But in winter there is little sun anyway, so photovoltaics might not be very effective.

We simply need to decide between Option 1 or 2, and I would appreciate any competent advice. Above all, no ventilation box on the house, please.

Best regards,
Marko
ares8327 May 2016 10:45
By "step," I meant the price difference, which is an additional €1,500 compared to the €2,500 difference between the 404 and the 504. The 504 will probably consume less energy but likely won’t make up for the €2,500 difference. For me, the noise level is definitely worth some extra money, but another €1,500, like in your case, probably not.

For the BAFA innovation subsidy (which is only available for new builds), I only see the 504 eligible.
B
bvlgari
27 May 2016 11:23
ares83 schrieb:


For BAFA, I see only the 504 available for innovation funding (which applies only to new builds).

I can only find this list for innovation funding, and the 304 is included there as well.
O
oleda222
27 May 2016 23:55
Only heat pumps listed on the Bafa list are eligible for funding, but not every heat pump on the list qualifies (only those with an annual performance factor of 4.5 or higher are supported)...
ares8328 May 2016 16:40
@Teyla Greetings to the neighborhood. I come from the heart of the LR ROW.
And thank you for the information regarding the noise levels.
Teyla28 May 2016 18:20
ares, it's funny to meet someone here from ROW as well

And then with the same profession as my husband
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bvlgari
30 May 2016 22:16
A possibly silly question: Can only the THZ504 be connected to a photovoltaic system, or can any high-energy appliance (including the THZ304) be connected to a photovoltaic system as well?

I am a bit confused by the following sentence (description of the 504) on the manufacturer’s website:

"
  • High independence: operation possible with self-produced photovoltaic electricity
"