Experiences with brine heat pump

You can definitely use it like that, looks suitable. Price?

I never understood why multiple branches are chosen. Here it is prescribed if a slab foundation without a basement and gas is included. Otherwise, you are free to decide how to lead the connections into the house. It costs €800 per unit, compulsorily to be procured from the supplier.

That can definitely be used like that, looks fitting. Price?

I've never really understood why multi-duct systems are chosen. Here it is prescribed when there's a slab-on-grade without a basement and gas is included. Otherwise, it's up to you how you lead the connections into the house.
It costs 800€ per unit, mandatory to be procured from the provider.

I can't say the price.. as a regular home builder, I would have simply rebuilt the "bracket" myself or had it rebuilt by the local steelworker.
But back then, multi-duct introduction wasn't really well known for us.
But I think the multi-duct introduction is something, especially regarding tightness, where craftsmen can't really go wrong.

P.S. for us, the supply and return of our air heat pump are led through the basement wall with two kg pipes and sealed with a special dorma screw seal. That would have also worked through the slab-on-grade...

Hello dear community,

I would like to get an opinion from the experienced heat pump experts here in the forum regarding the efficiency of my brine-water heat pump.

It has been running since around October 2015 (shell construction, drying & remaining construction work until March 2016), normal operation thereafter.

A KfW70 house is heated:

- 265m² usable building area, 2 full floors, insulated attic
- window ventilation
- brick walls + 160mm composite thermal insulation system
- final energy demand building 22 kWh / m² a
- primary energy demand 45 kWh / m² a

Heating system:

- Novelan WS 10.2 H3M
- 2x deep boreholes 85m
- 180 liter hot water tank (at 52 degrees)

Unfortunately, I only get log data from my Novelan regarding the amount of heat and running time of the pumps (see attachment). The electricity demand is unfortunately mixed in the bidirectional meter with photovoltaic generation and many other consumers.

I would be glad if someone with more expertise could interpret the values over the 3 winters somewhat better than I can. Do the consumption values for the heat match the data in the energy certificate? Are the operating hours of the heat pump reasonable?

Otherwise, I can’t proceed without a separate electricity meter for the heating. Maybe the given data is at least sufficient for a rough assessment regarding the efficiency.

Thanks and best regards

Without a separate electricity meter for your heat pump, nothing can be said about the efficiency. Only by the compressor starts can one say whether this heat pump runs durably (and does not short cycle).

Hello Mastermind,

how would the compressor starts on my heat pump and the operating hours be assessed?

Best regards and thanks for the feedback

Hello Mastermind,

how would the compressor starts for my heat pump and the operating hours be assessed?

Best regards and thanks for the feedback

Certain key data are still missing. Is a heating load calculation available?

A compressor is usually designed for a lifespan of about 100,000 starts.
A brine heat pump should operate about 1,500-1,800 hours per year. Since you cannot clearly separate the numbers, it may be that they are distorted by screed heating or something else.
Therefore, it is best to record year by year or month by month.

The usual tricky questions?

How was the size of the heat pump determined?
Buffer tank yes/no
Individual room controller yes/no
How is the hot water produced, at what temperature?

P.S. You basically can’t avoid having a separate electricity meter for the heat pump.
A simple meter is sufficient for this, or an S0 meter or something similar... Meters cost about €50-100.
Installation by an electrician takes 30 minutes.... Done