Choosing Best Gas Stove for 200m2 Single-Family Home with Underfloor Heating, 3-pane Windows

Hello.
I need help in choosing a gas stove for a single-family house, total 200m2, usable 150m2. Downstairs I have underfloor heating in the living room and kitchen + corridor + bathroom, the rest radiators and upstairs, the corridor + bathroom flooring, the rest radiators. Insulated house, 20cm styro graphite. 3-pane windows currently the best quality on the market. Roof insulated with wool 20cm. I am asking for suggestions which stove will give me the best results in gas consumption. I would like to add that I am using the 2 + 1 family model. What annual gas consumption can I count on with such warming and space ???

And probably done on two circuits. So down and Gora. A typical solution used by plumbers who have been doing this for years and do not want to feel new solutions. Typical solution for a steel-fueled boiler.
If it is such a solution, it will be difficult to precisely adjust and obtain comfort everywhere while maintaining a moderate demand for gas.
So what kind of boiler? Take one - what service you have close at hand.

I talked to a few plumbers about this and they say that it is a matter of fine-tuning everything, not a problem that it is on 2 circuits but ok. And as for the help in choosing a stove, do you have any experience with a boiler? Do you recommend something? Or is it only the distance to the site that you are suggesting?

Of course, according to them, there is no. They don't care how much you pay for gas. You set a bigger parameter and it goes. At most, the thermostatic valve at the floor heating (because they probably pressed you) will "cut". And that the condensation will be less or not at all - it is probably less important.
Approx. Does not matter. You've already done it - it's hard.
It is most convenient for the boiler and it will not be the most economical.
It is better to control the high temperature and low temperature circuits separately. For this also the control of the mountain - down.
If you want to get even relative savings on what you have, give larger (oversized) radiators. Then you let a low heating parameter go everywhere, and the condensation will be easier to control it.

And the boiler itself. The main criterion is the availability of the service close to home and the price of spare parts - because sooner or later something will have to be replaced.
You will probably find the average prices of spare parts online for most brands.

Personally, I think the De Dietrich - especially the Lumea MPX - is quite good value for money. But I know that this brand has its supporters and opponents - just like any other brand. Soon someone will write that Termet is good and cheap, and nothing will convince me of this company.

The heaters are of the highest caliber, so I think it will be ok. The heaters can go directly from the boiler at the lowest possible temperature and then the floor on the mixing system? I understand well? What do you think about the Buderus GB172 and the tray 120?

GB172 is a good boiler. If you have a good service nearby, get it. A 120l container for such a family model should also be enough. Well, unless you plan to pour water into two bathtubs at the same time, it might not be enough to blow.

zales.vip wrote:

GB172 is a good boiler. If you have a good service nearby, get it. A 120l container for such a family model should also be enough. Well, unless you plan to pour water into two bathtubs at the same time, it might not be enough to blow.

Unfortunately, the service is 100 km. I have a Viessmann service on site, but I don't know if they are good boilers. Is there any alternative from Viessmann to the GB172 ??

Any modern gas boiler from any company will cope with this task. I recommend and often install a termeta.

And what about the choice of a furnace in terms of the minimum kW power generated by the boiler, which in Buderus GB172 is at the level of 3kW - 20kW and, for example, a wiessman has 6kW -21kW, i.e. Buderus should burn less gas with less demand due to the fact that it will not have to be so often turned on and off. Right or am I wrong?

Then maybe start with what companies you have a service nearby and we will choose something from these companies.
The 100km service is a bit of a shame. Everything is nice and beautiful as the service technician is to come to "clean" the boiler. It's worse when something rains in the season and you wait 2 weeks for arrival.
Of course, after the warranty, there are still "independent" service technicians.
Lower minimum power means that with lower heat demand - the boiler will turn off and on less often.

So they slept less then?

Fewer starts means greater savings and failure-free operation. Some boilers are turned on at intermediate power and only after some time (several to several dozen seconds) go down to the minimum power (eg Vitodens 050). And when they keep the heat at a minimum - they are more economical.
And the board goes through fewer startup cycles - it should last a bit longer.

Here, I would focus more on good automation and the separation of floor and radiator circuits than on the minimum power of the boiler, which is also important, but not the most important.

Andrzej lukaszewicz - automation of course yes. But with a well-insulated house, sooner or later the boiler will go down to its minimum. And the smaller this minimum is, the better.
As much as the minimum power will be too high to what automation would not be - the laws of physics will not deceive. It is all about the demand and supply of heat. If the supply is greater than the demand, automation will do nothing.
Out of curiosity, what is the lowest power of Termet Silver or Gold?

3-20kW. Typical decent modulation range.

In my opinion, from 3 to 20 it is very good because from what I can see some boilers start from 5-6 kW to 20-21 kW

And they cost 1.5-2 x as much, but the magic of the badge and good marketing ...

But for some, build quality is different.
Termet - it is cheap and good because it is good and cheap.
He is'nt bad.
However, it is worth checking what we get for what price. Sometimes a similar, but more expensive boiler offers more extensive automation - even in the "standard" one, and the cheaper one - to implement the same functions, it needs additional automation and expansion cards.

But I agree, but I do not recommend people fancy boilers for simple applications. That is why I wrote that automation and the whole concept are more important than the minimum power and the choice of the boiler brand, "because the service is close".
And I often see expensive boilers installed that have everything, control of pumps, mixers, etc., and pumps plugged into a socket. We still have a lot of such installers, dilettantes-pullers.

In any case, I do not recommend Viessmann Vitodens 050. Only problems from the beginning of the installation. The stove freezes, error Fd must be reset once a day. the service is spreading its hands: "this type is like that, maybe if you replace the motherboard for 2k, maybe it will help".
the drama has been going on for several years now.

Unhappy_user wrote:

"This type has it, maybe if you replace the motherboard for 2k, maybe it will help."
the drama has been going on for several years now.

Write down how much the boiler cost, why did you buy it, did someone recommend it?

well, it was around 5-6k back then. The installer convinced me. The Viessmann brand was also important to me. Now I regret it, but due to the emergency situation in my mother's house, I had to decide quickly.

Hello, I am asking about the Vitodens 050 W boiler just mentioned above. Previous statements are from 2020, now we have 2023, I called the Viessmann service and a very nice man. He explained to me that yes, there was a problem with maintaining pressure, etc. some hoses and seals were replaced and now it's good. Does anyone confirm this? In general, I am facing the need to replace the solid fuel boiler because it has burnt out and water is leaking from it (MPM DS 12-14 from 2015, launched in spring 2016) with a gas one. The house is a terraced house, unfortunately and fortunately extreme. Pretty well insulated. There are 3 floors, of which the ground floor, i.e. the garage, the boiler room, I do not heat, although the radiators and the installation are done. So I heat 2 floors, about 80m2 each. Flooring only in bathrooms on RTL, the rest - KERMI X2 radiators, all on tees. There is a Kospel W5W 140 liter tank, but with a double-function boiler it will probably be redundant (unless I'm mistaken). I must admit that the price of a condensing boiler is important to me, which is why I am interested in the Vitodens 050 W, which currently costs about PLN 3,800, and I have read a lot of good things about it. I can't afford anything much more expensive at the moment (difficult situation) and the need to install a chimney liner, installation, gas connection, installation design, etc. I will ask the installer about the possibility of connecting the boiler without temporarily disconnecting the old boiler, which I would like to still use to heat DHW water because I have quite a lot of wood left to light the coal, so I would use the old boiler for another year to add water. Anyone give some advice? Regards

And this Kospel is hanging or standing?

Added after 9 [hours] 19 [minutes]:

You want to use the Vitodens 050 boiler - and it is a combi boiler, i.e. it heats water in a flow. Until now, you had a DHW tank, I don't know if DHW circulation was connected to it or not (forced DHW circulation in the tubes so that DHW was quickly available in the tap). You cannot connect such circulation to combi boilers. In addition, each combi boiler has a limited amount of water that can be heated on a regular basis - when one person takes a shower, the other cannot use hot water. In the case of the HUW tank, such restrictions do not occur. Only then must the boiler be single-function to cooperate with the HUW tank.
You had a solid fuel boiler - there are probably some pumps in the boiler room - maybe an expansion vessel and a safety valve if it was a closed system. In this case, consider using a standing gas condensing boiler - Saunier Duval Bear Condens - there are several threads on the forum about these boilers - specially designed to replace old boilers - here is a link to the manufacturer's website: link
and an article about these boilers: link
and here for the price: link
In the case of such a boiler, the maximum power of 18kW is enough and then you can lead the chimney through the wall.