We don't have underfloor heating. The heating and cooling is done through vents and ducts. I don't know how to translate the type of system we have into English but it is basically a heat exchanger, brings in the air from outside and cools it in summer. It is possible to cool it up to 10 degrees. The system is from Germany, as our house was built by a German company. (in 2009)
An added feature is that we can use pollen filters in the system in summer, which is very helpful for allergy sufferers.
The daytime temperatures in the past few weeks have been in the high 20s and low 30s. It has been quite humid out as well. Our house is about 21 degrees. There are 3 levels, each level has its own unit (all units are in the technical room indoors) with a main control with each room having its own temperature control. The floors are cool, but not really cold.
In winter the air is heated. I do miss underfloor heating but the benefits in summer make up for this. Also in winter the advantage is you can change the temperature in each room rather quickly.
In our previous homes, where the summers were becoming unbearable, we contemplated installing an air conditioner or two, but it was complicated and more than likely some neighbour would have objected. We used fans and dehumidifiers, which helped somewhat. When it was really bad we escaped to the mountains. The hardest part was coming back home!
Summers are getting hotter. I see a lot of new builds with "active" cooling, which is in the underfloor heating from the outset. How effective it is I honestly don't know.
For us, as we were building new, the difference between a traditional heat pump and a reversible one wasn't very expensive, so we decided spend a little extra and get the one with a cooling mode as well. We have underfloor heating / cooling.
The problem is that we have a lot of glass in our house, so when it's 30C outside, rooms on the southern side of the house can reach 40C+. No amount of reversible cooling is going to make those rooms comfortable.
The long awaited quote from Romande energy is 5,750. A little more than we want to pay, but a lot cheaper than a full blown aircon system (Pun intended)
It would if you would cool down your floor too much. That is why usually the supply temperature is limited to at least the dew point plus some reserve. e.g. min 18°C. Of course, your floor will probably never cool down to 18°C so you are safe.
But condensation is the main reason why underfloor cooling is greatly limited.
Slightly OT here, but This Old House has some mid-70s vintage windows. They are good quality double-pane solid wood, so we didn't want to replace them. However, they could use some help in that blaring Alpine summer sun. We installed film from an outfit called Velken (DE). It comes in 3 reflective styles; you tell them your measurements and they cut to fit. Bit tricky to install, but after one, we were experts--it's a 2-person job. You can now stand at those windows on a sunny summer day and feel absolutely no heat coming through. (We consciously left some windows unfilmed so we get the benefit of low winter sun. They can be covered with exterior shades in summer.)
So the heat pump you have now is not "luft/wasser"? That might be a better option.
Who is the manufacturer of the current heat pump? Are they the ones you already spoke to?
Do you have underfloor heating? If you do and the house is older the floor hoses might not be ideal for a cooling system. At least that is what we were told in our previous home.
We only have 3 solar panels providing our hot water. There is of course a boiler. Have to check the size but we never run out.
A word of caution. When we looked into active cooling under the floors we were told it is only going to bring the temperature down by a few degrees. It is not air con. This is why some people do air con with solar panels, but then you need a battery for sure as many people will run aircon at night so they can sleep in a cooler room.
There are many companies who can install a new system. There are also "energy consultants" (at least in Aargau there were) who can advise you about your options. Also worth looking into are the rebates available, possibly on several levels) for new installations of solar panels. There are many companies offering this now so perhaps something to prioritize. Some companies offer financing.
The current heatpump is from Störi Mantel and is labelled as such. The company still exists but not sure they are capable of a hybrid system. I spoke with them but it took them a month to give an offer..not impressive.
The house is 25 years old, the under-floor piping would be fine for cooling. We don't want air-con if we can avoid it, just a comfortable temperature.
I have experience with Stiebel Eltron and Viessmann.
With Stiebel Eltron we replaced a luft/wasser heat pump from 1990 with a newer one which could also heat the hot water.
With Viessmann we had a service contract on the replacement model of a 1984 "grundwasser" heat pump.
Both companies work with partners who do the installation but the websites will give you an idea of the product range. Perhaps others have recommendations for you.
As for waiting a month for a quote, that is unfortunately becoming quite the norm here. Sometimes we are lucky to get a quote at all! I ask myself why they bother sending someone out in the first place.
We have a heat pump that has the cooling option and also a hot water tank plus overflow tank from Viessmann. The original company who made our heat pump has been taken over by Viessmann. We're on a service contract with EWZ but on the couple of occasions they have had issues they have sent the folks from Niedermann in Baar https://niedermann-ag.ch to fix it - and they come across as very competent and professional.
Our house is Minergie standard and we have wall to wall south facing windows and as long as the blinds are kept down during the main part of the day then the house stays lovely & cool.
If you have room and budget solar thermal is worth looking at, then use the warm pump as back up heating. Jenni make the heat exchanger and has installers on their website.