Experience with KFW55 solid + gas + 5 sqm solar

Brief update: The consumption has stabilized a bit downward again over the past 12 months. For the next 12 months, I am planning €28/month for heating + hot water costs. Overall, I am very happy with it, as I continue to heat every room to 22-23°C and the bathroom to 23-24°C. There is also no night setback in our home.

My gas supply contract is ending again for this year. I am surprised and pleased by the low consumption of 7100kwh.

Small update:

Currently €38 monthly installment for gas.
Consumption 2019 to 2020 was 6,400kWh
Temperature consistently 22-23 Celsius in all rooms except the bathroom, where it is 24-25 Celsius.
( No nighttime setback )

I am satisfied.

Our house has so far withstood weather and so on well, after all we have been living here for 7 years.
The only defect is fine cracks in the walls, most likely due to unprofessional craftsmanship. For example, no mesh was embedded.
The exterior plaster shows no cracks, so I claim the movements in the masonry are of a normal nature.

At some point we will renovate... once the loan is paid off.

Speaking of the loan, we are currently working on a few optimizations.

Immediate loan (0.61%, 44k)
Forward loan 07/2023 (0.84%, 43k)
Forward loan 01/2026 (1.45%)

It can happen that fast. Just got a comparison offer from the current bank (much too expensive) and suddenly the interest rates go up by 0.2%... grr

There is news!

Over 12 months, we have an average gas consumption of 8000 kWh.
In the harsh February, it is 45-75 kWh daily, depending on the cold.

The attic is often unbearably warm, so we would like to air-condition the bedroom, children's room, and office with split air conditioning.
And also install an indoor unit in the living room with open kitchen on the ground floor.

Outdoor unit
CU-4Z68TBE

Master bedroom (12sqm East-South)
CS-Z20XKEW

Children's room (12sqm West-North)
CS-Z25XKEW

Office (12sqm South-West)
CS-Z35XKEW

Living room (35sqm + 15sqm kitchen)
CS-Z35XKEW

I would also like to use it for heating, so not just cooling. Now that gas has become very expensive, it is definitely worthwhile with such a high-quality modern air conditioner. Of course, it makes no sense when it's -10 degrees outside. But if the gas supply is suddenly cut off for us private individuals, I have a working fallback, even if the usual 23 degrees cannot be reached everywhere with only one device on the ground floor. But as an emergency operation, it is certainly suitable.

What do you think of the expansion plans?

The idea itself is good - but the devices are chosen too large. I would take 2 kW everywhere (if they already exist, often 2.5 is the minimum) and if you want to be on the safe side, 2.5 in the living room. Single-splits are by the way cheaper (shorter line lengths, devices cheaper), more comfortable (because they cycle less) and more redundant than multi-splits. You just have to find a place for all the AGs... Maybe mix them?