ᐅ Ground Source Heat Pump, Solar Panels, and Fireplace for Heating?

Hello everyone,

after doing some research, I’m now completely confused.

I called the developer and they said: We first need to do a heat demand calculation, but basically, 0.035 W/m² should be used.

Then I called the manufacturer:
The heat pump provides 3 to 3.5 kW (the demand is approximately 4.5 kW for 136 m² (1460 sq ft) – no basement) and should be sufficient when combined with heat recovery and the overall system.
We were already thinking about installing tiles everywhere – I heard they can add a few more watts.

A friend of mine said he pays about 1000 euros per year for natural gas for a three-family house. Now I’m wondering if we should switch to a gas boiler plus solar system and only use the underfloor heating.

Theoretically, the 3 kW ground source heat pump with ventilation and a fireplace should be enough...

or is it not?

Help!

Best regards,
Haunt

Edit:

According to the manufacturer, the ground source water heat pump provides 3.5 kW and the electric backup heater is 2 kW, which should also be sufficient for an external hot water tank...

haunt schrieb:
...after researching, I am completely confused

A very bad starting point!

haunt schrieb:
...We first need to do a heating demand calculation, but basically 0.035 W/m² should be used

Well, something seems seriously wrong here. Demand means energy (kWh), power means kW!

haunt schrieb:
...The heat pump delivers 3 to 3.5 kW (demand is about 4.5 kW for 136 m² (1463 ft²) - no basement) and should be achievable with heat recovery and the overall system.

How do you think a judge would interpret “should”?

haunt schrieb:
...We were already considering installing tiles everywhere – these should add a few watts as well.

How could that be physically possible?

haunt schrieb:
...Theoretically, the 3 kW brine heat pump with ventilation + chimney is completely sufficient...

Has the heating load calculation including the thermally effective air volume flows resulted in 3 kW? Which brine heat pump has a heating capacity of 3 kW? Please provide the manufacturer data! Also, a brine heat pump must operate without an electric heater! Is domestic hot water production taken into account?

haunt schrieb:
...Help!

You urgently need help; otherwise, you’re building a money pit!

Best regards.

You urgently need this, otherwise you’re working on a money pit!

I’m already thinking about switching back to gas...

But first, thanks for the reply!

I would like to understand it better:

So according to the manufacturer

First, the brine heat pump:
Type Item number Power (kW) B0/W35 Electric heater (kW)
JVP3 740023 3.5 2.0

This is a complete Nilan JVP 3 Compact package.

Then there is the ventilation system:
- Heat transfer capacity depending on air volume: up to about 2 kW

So far, everything looks good to me. We want to build a KfW 70 energy-efficient house.

According to my calculations, we have a demand of about 4.7 (apples, pears, bananas) and the complete system delivers 3.5 (power) + 2 (electric heater) + about 2 (heat recovery).

In addition, there is the underfloor heating with tiles, and no basement.

From what I could find online, this should not be bad. But these are more or less the statements from the manufacturers.

I just looked up the term “energy consultant” in the phone book...

Did the heating load calculation considering the thermally effective air volume flow result in 3 kW?

Did I mention I’m a layperson?

haunt schrieb:
...Did I already mention that I’m an amateur?

That’s not necessary, as it’s clearly obvious.

haunt schrieb:
...First, the brine heat pump:
Type Item number Output (kW) B0/W35 Heating element (kW)
JVP3 740023 3.5 2.0

As mentioned before, if the heating load is ≤ 3.5 kW, that might work. However, there are likely to be significant problems with domestic hot water preparation here.

haunt schrieb:
...
Then there is the ventilation system:
- Heat transfer capacity depending on air volume: up to approx. 2 kW

What exactly is “heat transfer capacity”? Advertising? 2 kW is quite a lot. How is that supposed to be realized in a single-family home?

haunt schrieb:
...The whole setup looks good to me at first. We want to build a KfW 70 house.

Well, then my condolences!

haunt schrieb:
...According to my calculation, we need about 4.7 (apples, pears, bananas) and the entire system delivers 3.5 (output) + 2 (heating element) + approx. 2 (heat recovery)

I would reconsider that. Your own calculation, saving money instead of getting an accurate dimensioning? Good luck with your budget!

Best regards

I think we’re talking past each other.

This is just a rough, preliminary estimate to see if this could work at all!

Own calculation, saving money for an exact sizing?

On Thursday, I will meet with the builder to discuss everything. This pump was listed as an option for the house. We’re building a turnkey property.
The precise sizing will come later – am I thinking about the heating system too early now?

Well, my condolences then!

Why is that?


Best regards,

haunt

haunt schrieb:
....On Thursday, I will meet with the developer to discuss everything. This pump was listed as an option for the house.

I probably find it hard to put myself in the position of a layperson. How can this or any other heat pump be offered as an option if there is no heating load calculation? That makes absolutely no sense.
Proper planning looks something like this:

haunt schrieb:
....The exact sizing will follow later – am I worrying about the heating system one step too early?

You really can’t start too early with this.

Best regards.