Best Wash Basin Water Heater: Hydraulic vs Electronic, Siemens DE06101 vs Stiebel Eltron DEM 6

Hello.
I am going to buy an electric instantaneous water heater and therefore have a request for suggestions on the following:
1. Hydraulic or electronic control?
2. Heater "resistance wire", uncovered?
3. I mean DE06101 6 SIEMENS or DEM 6 STIEBEL ELTRON, but in the case of Eltron I did not find any opinion on the network, and it seems to be better, because it has water temperature regulation.
I read on the forum about Clage, but they are much more expensive, especially electronics.

The most important question: do you have what to power it with? I say right away that you will not connect it to an ordinary socket.

The main thing is where you want to install this heater (garage, company, washbasin, shower, how many points you want to supply) and how often you will use it.

For example: 6KW is quite a lot for a wash basin or under a sink because the usable temperature at such a collection point is about 35 degrees.
As Magister_123 noted, you will need 32A security if you use it in a separate circuit. Maybe that big is not needed?

The advantage of electronic control is that the device turns on at a lower water flow (about 2l / min), it has a PID controller to control the power in relation to the set temperature (the inlet water temperature and flow are also taken into account) - this is one of the important features of electronic control .
If you want to use it sporadically, e.g. in a garage, it might be better to buy a cheaper hydraulic one, unless you want to be more eco-friendly. In the case of the hydraulic, you will find a switch with power levels and possibly an economy mode rather than smooth temperature control. If the water is too hot, you must mix it with cold on the tap. In an electronic one, you can use a single tap if you don't need cold water - that's the main difference in the operation itself.
There are a lot of producers on the market, including our domestic ones (apart from the heaters you mentioned, there is also a company from Koszalin, but I have not had any contact with their products live. The prices will be rather similar depending on the power and control).

I only need the heater for the washbasin in the bathroom, so it can be used several times a day. He has been using a Siemens DH 04101 3.5 kW for several years and to be honest I am not thrilled. Especially in winter. Then it does not heat the water (despite the flow restriction on the valve). In addition, from the very beginning I was weakened by its "inertia", especially the temperature jumps after turning the tap on and on again. Perhaps hence my exaggeration with power, but I assume that the "electronics" takes power according to the flow and the "plumber" is always full. Thank you for noticing the installations because I have a separate 3x2.5 circuit, but the protection is only 20A.
I know about the company from Koszalin and I was thinking about AMICUS EPO.D-5, but even in their manual I have not read about the control, however, since it says "water temperature control with the flow rate", it is probably rather hydraulic and the cheapest electronic ones have over PLN 700 (5kW) .

So 3.5kW max

There is no place for a boiler? Or a gas heater?

If you have it on a separate circuit and 3x2.5mm2 cable, you can connect a 5KW receiver, you only need to change the differential to 25A
Unfortunately, temperature inertia will occur. It is certainly more noticeable when the inlet water temperature is about 4 - 7 degrees and you need to raise it by 31. The inertia is also influenced by the length of the hose connecting the outlet with the tap, so they are installed under the sinks, e.g. in cabinets, and connected with a flexible hose.
The higher the power of the heater, the switch-on threshold will be at a higher flow, so if you buy an electronic one, the valve capacity in the tap will have a bearing on the maximum power of the device (it may happen that it will not work at full power anyway). Therefore, some heaters are dedicated to two collection points with the possibility of simultaneous operation. Additionally, aerators are installed to limit this flow.

If you are not sure whether the heater is hydraulic or electronic, check the manual and check from which water source the device can be powered. If there is only cold water, it is a device with hydraulic control, if it can work as a DHW buffer, it means that it has electronic control.

If you want to have a power reserve that you can use in winter, you should rather invest in an electronic heater with more power.
You must know that despite the power reserve, in winter you will feel the increased inertia in the electronic control. Because the sensor at the inlet will measure the temperature of the water heated in the pipes from the environment, it will not switch on with full power. Then, when the temperature starts to decrease, the PID derivative will try to "predict" the conditions and start increasing power, then until the inlet water temperature is stabilized, the power will increase. As a result, water with a higher temperature than the set temperature will run for some time.

I wrote this because I see that in some way it is important to you, even though it is only washing your hands, but it is so short-lived that, unfortunately, all unfavorable phenomena will occur here.

setar wrote:

If you have it on a separate circuit and 3x2.5mm2 cable, you can connect a 5KW receiver, you only need to change the differential to 25A

Kaz1965 wrote:

Thank you for noticing the installations because I have a separate 3x2.5 circuit, but the protection is only 20A.

And what now?

technikabasenowa wrote:

And what now?

What do you mean?

A colleague Kaz1965 wanted to connect a 6KW heater on a 2.5mm2 cable ??

Now it has a 3.5KW heater and a maximum of 5KW can be connected on this cable,
With the protection it now has 20A, a maximum of 4.3KW

I think that you can buy a 4KW, 4.5KW heater on the market.

setar wrote:

technikabasenowa wrote:

And what now?

What do you mean?

A colleague Kaz1965 wanted to connect a 6KW heater on a 2.5mm2 cable ??

Now it has a 3.5KW heater and a maximum of 5KW can be connected on this cable,
With the protection it now has 20A, a maximum of 4.3KW

I think that you can buy a 4KW, 4.5KW heater on the market.

And secures the earlier ones?
If it will withstand this 20A, there is a good chance that other protections will work
Let the author specify the power supply he has, and so on

technikabasenowa wrote:

And secures the earlier ones?

The author of the thread wrote that it is a separate circuit, so the earlier one is just a pre-meter protection

technikabasenowa wrote:

If it will withstand this 20A, there is a good chance that other protections will work

Now I have already guessed why my friend assumed that 3.5KW is the maximum, despite the cable cross-section and 20A protection, allowing for 4.6KW to be pulled.
On the other hand, someone in the project probably included this heater, even if it was to be max 3.5KW, assuming that the power allocation is 5KW, it would not be possible to turn on the electric kettle . it sounds a bit grotesque.

For my part, everything on this topic. I greet everyone
Krzysiek