Maybe Rickard has the numbers ready However I believe the 5 kW is way too small for the Vasa region, at least with this kind of house. I looked for some topics regarding pump dimensioning for similar houses in the Umeå region and they seem to be around 7-8 kW. It's always better to go for a few meters extra when drilling the hole, you won't regret it.

Hello,
To get an idea what you need, some more information would be necessary.
The westcoast is long so is it Turku ,Vaasa or futher north? Is the house just one floor and shall the garage also be heated with the heatpump? What´s the distance between the house and the garage or is it in the same building?  Is the heatsystem pipes in the floor or is it radiators. If radiators is it a low temperature system, less than 45-50° water temperature when it is really cold outside.
What I can tell you directly is that the 5 kW-pump is probably to small.
Is the house already built or can you still make changes?
Another idea common in modern buildings with mechanical ventilation is to use an exhaust air heat pump. In this case you use the outgoing air to heat the house and the warmwater. You don´t have to drill any hole, that means lower cost. But the house must be well insulated. Read more about this type at www.nibe.se and choose GB in th left hand corner for english. Read about the types Fighter 360P and 410P as an exemple.

Hello.

I was wondering if anyone would be able to say, what size of pump is the most suitable to my new house.
I have been thinking about buying Nibe 1220 (=1230 in Sweden), but I am not so confident that Finnish pump dealers know how to calculate the optimum size of pump and hole for my house. In Finland the knowledge about optimum sized pump is not yet at the same level as in Sweden, so I thought I would ask you, because you are more experienced.

As I told before, I am building a new house at the west coast of Finland. House is a "concrete" house, made of Siporex. There is 163m² (+ 50m² garage). Volume of the building is 630m³ (+ 125m³ garage).
there are two showers and no bath tubb. Four or five people will be moving in when finished. The is also a fireplace, but mainly for decoration purposes. Ventilation is done with machine where is water based pre warming system.

Finnish dealers have calculated very different size of pumps and holes with these same informations depending of pump manufacturer. Examples:

Nibe 1210 - 5,
IVT HT+ C7,
Carrier heat60 C7,
LämpöÄssä V9,
Thermia Dipl. TWS 12.

so there is guite a wide range of pumps
Hole depths are also rangeing from 150m to 210m.

What is your opinion? What size of pump should I buy? and what size of hole it requires?

Please answer in English. My Swedish is terrible, if possible worse than my English