Junkers Euroline ZW/ZS 23 KE Gas Stove: Replacement Options for Disabled Homeowners

I warmly welcome.
I would like to ask for help. I have a double-function gas stove Junkers euroline ZW / ZS 23 KE. The stove is 15 years old and still breaks down (currently the control board has "pants" - the stove itself can turn on or you want to turn it off, it turns on and does not heat well water, only lukewarm flies, sometimes warm). I want to replace it, but I do not overly appreciate it. In addition, I live in a house with my mother, we are both disabled (we move in wheelchairs) and we do not have much to drive and ask for different heating methods.
We live in a single-family house, about 100 m2, with a non-usable attic, built in about 2000. We pay bills a lot because in winter about 700 PLN / month. Plastic windows, insulated building, I just do not know what in the attic, because we have no way to check. In the bathroom we also have underfloor heating. I do not know what else to write.
I read a little and I know that this furnace has an open combustion chamber. I want to buy a relatively cheap furnace, but also the amount of bills is important, because I would like them to be as low as possible.
Is there any sense in general to play in a condensing oven and buy the cheapest with an open chamber? Is it better to spend a bit more and yet condensation? Only just - unless you need additional pipes to buy and I do not know what the overall cost is.
Are condensing ovens really better? I do not know how this condensate works, I always set it to the minimum heat on an ordinary stove. Would it be efficient then?
I found such a stove, it costs 3500 zlotys on the Allegro. http://beretta.pl/produkt/ciao-green-25-csi-2 is it worth attention? Maybe you know some other better, of course, as the cheapest.
Sorry, so chaotic. I count on your advice very much. If you need any more information, of course I will answer.

greetings
Agnes

In fact, currently a gas condensing boiler is a standard. Boilers with an open combustion chamber are a dying species
Therefore, when it comes to replacing the new one, only condensate remains.

Condensing boilers like to work at low temperatures, if the installation, i.e. radiators, are adapted to this.
When mounting them, you need to remember that they need a chimney flange, which means replacing with a new one or inserting a second pipe.
They have so-called the closed combustion chamber, so the fresh air supply is no longer so important in the combustion process.
Condensing boilers also have higher efficiency, a larger modulation range, so you can expect a bit smaller bills and greater thermal comfort, because due to the larger modulation range, the boiler will turn power so that the burner walks as long as possible and thus provide hot water to the radiators as long as possible.
In addition, the condensate must be drained into the canister, which means that an additional pipe must be run into the canalization.
With condensate, it is important to have periodic servicing, so you have to take care of the service technician's visits and it is not worth saving in this regard.

As for the boilers, I do not know myself, so I will not say how much this "Beret" is OK. Generally, a new condensing boiler with an average low shelf requires 3-4 thousand. and for 10 years should be enough.

BUCKS wrote:

Condensing boilers like to work at low temperatures, if the installation, i.e. radiators, are adapted to this.

What does it mean? I have ordinary heaters. Will I need to exchange them?

The point is that the producers give the highest efficiency of condensates for water parameters 50/30, that is, the water has 50 degrees on the supply, and 30 degrees on the return from the radiator.
In general, 30 degrees on the return is a low temperature.
For boilers with an open combustion chamber, it is better that this temperature is higher, eg 70/55 degrees, because they are not designed to work at such low temperatures and thus can corrode faster.
It seems that if the return temperature will exceed approx. 57 degrees, the condensate starts to work as an ordinary non-condensing boiler, therefore in some situations it is worth thinking about replacing the radiators in order to obtain the highest possible efficiency on the condensing boiler, and thus optimize the costs, i.e. energy (gas) consumption and to increase comfort, because it is better if at the same power the heater will be warm rather than hot.

In turn, the water temperature affects the radiator power.
If the X radiator at 75/65 is 1000W, the same radiator with 50/30 water will only have approx. 300W.
If you want to get, for example, 600W, you have to raise the water temperature on the boiler or install a larger radiator, respectively. By raising the temperature, we reduce the efficiency of the condensing boiler and that's it.
Specially replace the radiators does not make sense but if we will modernize the radiators it is worth taking into account the fact that we have changed the open combustion chamber to condensate and give a tad bigger so that the return water usually had a value as close as 30 degrees.
By assumption, one can assume that if someone has a boiler with an open combustion chamber, there are rather no radiators adapted to 30 degrees on the return and such parameters will be too low to heat the room. But people also had a tendency to oversize radiators, so each case should be considered individually.

On the other hand, heaters in the design of the installation are selected to freeze temperatures of around -20 degrees (Gdańsk is in zone I, where you can take -16 degrees), and in Poland for the time being they are relatively warm, so you have a good chance that your radiators will work for most of the season at relatively low temperatures. The problem may appear as if it is cold winters, and this is probably only a matter of time.

I understand more or less what is going on. Radiators designed and bought a friend of a friend of a friend. I have no idea if they are enough. Only in my room is listed and I do not know if it is ok. I have about 200x40-45 cm, 2 "ribs", room 16 sq m, I am a putrid guy.

If I have junkers and have temperature diodes (45 degrees, 60, 75, 90) on it, then if the 45-degree diode is on, I can assume that the supply is 45 degrees? If so, how much would it be back on?

BUCKS wrote:

For boilers with an open combustion chamber, it is better that this temperature is higher, eg 70/55 degrees, because they are not designed to work at such low temperatures and thus can corrode faster.

This would probably explain why the heater in this oven looks like after World War 3 (and it was recommended to replace it 5 years ago). We always set the stove at the lowest temperature (about 1/4 knob), very rarely half, and I do not recall ever being up to the max. The 45 or 60 degree LED is the most common. Can I predict that the condensate will fulfill its role?
I'm sorry if these questions are stupid.

Is the programmer (temperature controller) a good idea?

piorunia wrote:

Only in my room is listed and I do not know if it is ok. I have about 200x40-45 cm, 2 "ribs", room 16 sq m, I am a putrid guy.

If I have junkers and have temperature diodes (45 degrees, 60, 75, 90) on it, then if the 45-degree diode is on, I can assume that the supply is 45 degrees? If so, how much would it be back on?

The radiator I assume is a plate, there are no 2 ribs, only 2 plates, and between these plates there are two layers of sheet metal acting as a heat sink for better heat transfer to the room and heating the air. Ribs remind me of old cast iron radiators. But this bent sheet is the ribbing of the radiator, so it's just a matter of proper naming, but probably we think about the same.
I do not know your boiler but you can assume that you had 40-60 degrees on power. As for the return temperature, if the boiler does not have a suitable sensor that shows the temperature, it remains checked, for example, using a pyrometer. Depending on the speed of the flowing water, the return can be, for example, 5, 10, 15, 20 degrees cooler. I suspect that it will be a difference of 5-10 degrees for you.

If so far, during these X years the maximum flow temperature was 40-60 degrees and the whole hut was warmed up, the radiators are OK.

Your questions are not stupid, because I see logical thinking and an attempt to draw conclusions.
I think it is worth buying a room regulator with an external temperature sensor, then the regulator controls the boiler taking into account the air temperature in the coldest room (usually the largest) and the outside temperature. At the beginning, there may be problems with adjusting the correct heating curve and it requires "fun" to change the settings to get to the heating curve that best suits your building's characteristics.
If you have radiators with valves and thermostatic heads, it should be remembered that in a room where there will be a regulator, the radiator should be without a thermostatic head, because it is the room regulator that replaces the operation of the head.