Air heat pump or use gas and solar?

Hello,

Hello,
specific question: Where can I find a good planner for heating, hot water, and ventilation for a single-family house to be built in 41812 Erkelenz?

For this, feel free to send me a private message or direct e-mail. The inquiry alone costs nothing!

Best regards

A rather old topic, but in my opinion still very current.

It has been said several times that a comparison between a gas condensing boiler or an air-to-water heat pump is only possible with a concrete energy demand calculation. However, some do not have such a calculation yet, for example because they are not that far along with the whole planning.

However, this is not an insignificant cost factor with the building services engineering and in my opinion it ultimately also affects the planning.

A dilemma then. You don’t want to spend money on planning before knowing what you will have. On the other hand, others cannot provide planning either.


What many of you should be able to do:
Your actual values.

- What type of heating do you have (gas condensing boiler, air-to-water heat pump, other)?
- What were the acquisition costs?
- Do you have controlled residential ventilation and/or underfloor heating (underfloor heating)?
- How many sqm of heated floor area do you have?
- What is your annual consumption (in kWh and euros) on average?


In this thread I have already read the following examples. Here is my subjective assessment:

- 600-800€/year for air-to-water heat pump (sounds very low after some research)
- at least 1000€/year for air-to-water heat pump (seems to be the most common opinion)
- 200€/month for gas (that sounds high)
- 200€/year more than for air-to-water heat pump (that sounds too little for a whole year)
- 120€-140€/month for gas (sounds quite reasonable)
- at least 1200€/year for air-to-water heat pump (sounds high)


If I try to take an average by eye, about 1000€/year electricity costs just for the air-to-water heat pump (plus electricity costs for the house) sounds quite realistic.

Gas costs are then around 1500€/year.

Calculated over 20 years, that would be a saving of 10,000€.
A Buderus Logamax Plus (an offer from a general contractor to me) costs about 1500€ according to Google, 2500€ connection costs plus installation, so let's say 5000€.

The air-to-water heat pump must therefore not cost more than 15,000€ for acquisition and installation or not more than 10,000€ more expensive than the gas solution, and then it only just pays off.
According to an offer from a general contractor to me, the air-to-water heat pump costs about 5000€ more. Therefore, it would be worthwhile.

But this calculation is now a fairly general statement without area specification, etc.
I would assume 150m² as an average.

I would therefore kindly ask you to bluntly share what it costs you (see the list above).
As a very rough guideline, to get a weak suspicion, this could help. Of course, it does not replace planning, but one still looks for such reference statements in order not to feel so much ripped off by the "experts."
And I think experience values are simply what many can use.

Hello

I am now writing my data here, although it does not quite fit your list, since we heat with geothermal energy (deep drilling).
Furthermore, in my opinion, in order for you to make something out of the data, it should be indicated how large the respective object is, how long it has been occupied (the first year usually always has a higher heating demand), and what standard prevails.

Size: 170 sqm
Occupied: since 11/2014
Standard: KfW70 according to the old Energy Saving Ordinance (2009)
Consumption: < 3,500 kWh (with the energy supplier we have prudently specified 4,000 kWh heat pump electricity for the next billing period = 72 euros p.m. = 864 euros p.a. including basic fee and without consideration of discounts).

(Electricity consumption heat pump for heating and water without support from self-produced photovoltaic power)

Hello Kaspatoo,

of course, it is interesting to compare consumption and cost values for the consideration of economic efficiency. You are right that demand planning naturally involves certain financial expenses. However, I believe that this is indispensable for the proper assessment of the right alternative for the respective situation. In principle, one can certainly deduce quite a bit from the actual situation. But I would be quite critical about what that means for the design or scenario evaluation.

Often the problem is that the existing heat generator in existing buildings is oversized or incorrectly adjusted, or the radiators are not hydraulically balanced. Taking an average from the information provided in the thread certainly distorts the whole further; in addition, there is the not to be underestimated point for domestic hot water preparation—especially in well-insulated buildings, the proportion becomes increasingly larger and certainly plays into the hands of condensing technology.

Best regards, Erik

Hello everyone,

I need your help or assessment. My architect offered me an air-to-water heat pump with underfloor heating. For me, a cost comparison (purchase/maintenance) with a gas boiler would now be interesting. The architect told me that the purchase costs, considering compliance with the Energy Saving Ordinance 2016 (with the gas boiler, a solar system for hot water as well as a heat recovery system would be necessary). The house is supposed to be 150 sqm. The air-to-water heat pump is a Stiebel Eltron air-to-water heat pump type WPL 10AC including an electric auxiliary heater of 8.8kW.

I hope the information is sufficient to see roughly what monthly costs need to be considered.

It would be nice to hear your assessments or experiences with an air-to-water heat pump.

Thank you!

That's simply too little information. It really depends on the house (insulation, energy standard, building type - e.g. windows, gable, bay window - etc. pp). You can't do more than guess - although I would already say that 8.8kW is oversized, but I don't know the design figure, and you probably don't have a heating load calculation yet either. You shouldn't commit to a system before that's calculated.

Since I moved in during the first half of 2014 into a KFW-70 house according to the energy saving ordinance (currently about standard) with about 180 sqm of heated area (+ about 60 unheated basement) I have needed a total of 3800 kWh for heating and hot water, but also with a ground-source heat pump. But you can already see a big difference compared to F-pno (if his figure is "per year"). How should one estimate your consumption there?