Help with the choice Sensor Plan Tube

[vidoc67]

Hello,

We are going to modify our heating system to switch to pellets and at the same time install solar panels for DHW backup.
Apart from the financial aspect, amortization and profitability ...
I'm looking for connoisseurs, experiences, pro? can help us elucidate a bp on the choice of sensors.

Here, out of 6 installers consulted for the boiler + solar quotes 2 have tubes (Tryba and Viessmann), the other 4 are plans, among these 4 also a Viessmman installer.

We are exposed more East-South-East, than the inclination of the roof and ~ 40 °, completely clear horizon, that we 3 people, that the mixed solar balloon will be 300L.
We live in the East near Strasbourg.

Using Viessmann for example, is it better to install 2 type 200-F flat panels for a surface of ~ 5M² or 1 type 200-T for 3M² ??

Viessmann installers are not consistent with each other.
A bit of support that the dishes will have no "yield" or close to zero, and that the tube is more appropriate with a bcp higher output (one can wonder if one does not work why the other would be bcp better. .. to hear it the diff would be quite substantial but here I am not very convinced).
The other tells us that it will work and that the difference in yield and price is not justified in my case. What do you think ?

I know the subject is vast ...

The simulation tools found on the net show little difference in performance ...

Last but not least, what if you had a choice between Viessmann and Sonnenkrfat?

Thank you for your help.

[the middle]

Hello vidoc,
It is clear, the vacuum sensors are more efficient.
I have a friend who is very happy with his planar sensors.
That said, for me, the most important thing, is having a system that empties the sensor when he is not working.
It helps prevent overheating, and most importantly, no antifreeze needed.
I hacked my assembly myself, with vacuum sensor, but that does not make me an expert in the matter

[sspid14]

Completely agree with the fair ...

The vacuum collectors are more efficient and can operate at lower temperatures (therefore longer during the year).
The only prob is the price ...

[vidoc67]

They are more efficient (c relative nonetheless?) But with an equal surface, in my case we go from 5m² for 2 flat collectors to 3m² for 1 tube ....

[the middle]

They are more efficient ( c relative all the same right? ) but with equal surface, in my case we go from 5m² for 2 flat collectors to 3m² for 1 tube ....

Well no (for me) the tubes sensors allow to work further in the seasons.
By cons, I do not know if the sensors with vacuum tube allow the emptying of the system when the sun is not present...
Personally at home, the sensor is with vacuum tubes, and when I go on vacation, I deflect the sensor on a radiator ...
The goal is not to go too high in T ° in the balloon.
It's a shame .. because I spend electricity for nothing, with the circulator ...
I did not follow the advice of a specialist who told me "but no, you will not go too high in T °, ​​you do not risk anything"
When I see the performance of my system ... I tell myself that this specialist is next to his pumps.
In good weather, with 200 liters of hot water, and a hot water consumption of 60 liters per day, I arrive at 70 ° C in one day !!
It means that in two days of sun, without using hot water, I reach 100 ° C for sure.
That's why I like the sensors that empty when stopped.
I insist on this point

[PITMIX]

Hi friends
This subject also interests me a lot. I don't know much about it except a few personal experiences.
I admit that for me the advantage goes to flat collectors since I can make it myself.
In Alsace there is no doubt that the flat collectors will work. You just have to see Christophe's house.

[I Citro]

I too am right in the quotes ...

I pass you the thoughts of the "pros" who say that tube collectors are too powerful...

What dummies.

The tubular is especially to be preferred when one is not due south.
You say you have a 40 ° slope, that's good. (I only have 20 °)
They can also be mounted vertically (against a wall) and their performance is high.

Do not oversize the sensor too much on the pretext that it is tubular ...

[the middle]

You say you have a 40 ° slope, that's good. (I only have 20 °)

I will say that there, the tubular is to his advantage

[Philippe Schutt]

The real price of solar:

https://www.econologie.com/fichiers/partager/1241637002qr7hbh.pdf

[Philippe Schutt]

The flat collectors remain interesting for the very aesthetic integration in the roofs, the tube collectors are superior in performance, and as the tubes are orientable, they allow to have a good output even when not being due south.

Often tube collectors have no water in the tube. I saw 3 types:
-with water circulation
-with a gas which evaporates and recondenses
-with a simple copper bar

The last 2 systems allow you to change a tube without emptying the circuit.

From a pure profitability point of view, it seems to me that photovoltaics is the most interesting. In any case, the sellers claim 7% per year.