Solar CESI, gel management?

[MathieuM68]

Bonjour.

I have a solar water heater Sonnenkraft, with tube collectors, and I live in the Herault (34)
The heat transfer liquid is water with the product (glycol I presume).

In the CESI manual, there is a sensor warm-up option to prevent freezing, as soon as the temperature drops below 4 ° (adjustable temperature)

They put that it is necessary as much as possible to avoid using it, because it uses the hot water of the water heater to reheat the sensors.

Do you have any idea what to do with this option?

Goods.

[Christophe]

Uh it seems to me fishy your indication, because when there is sun even if it freezes a solar system can sensor calories. In addition it is a comparator that manages the solar system: if your storage water is hotter than the panels never the circulator will turn!

So my advice: turns everything into a drainback system. That's what we have here!

With a drainback you have as advantages:
- solving the problem of freezing,
- resolution of overheating and over-pressure (loss of liquid),
- you can turn on normal water,
- you avoid a heat exchanger (you can make a system drainback with a simple balloon exchanger much cheaper),
- and cherry on the cake: you increase the life of your panels because they are never under pressure!

Attention must be certain that the panels are well emptied!

Only downside, you need a slightly more powerful pump, so it's slightly noisier ...

Here is our drain system, on the "solar" side only:



At the bottom right where there is the 2nd T ° probe, it is the "water" thermal buffer.

[MathieuM68]

Bonjour.

The principle of the option in question, it is precisely to restart the circulator as soon as the temperature of the panel drops below 4 °, to warm it precisely by pumping the calories of storage ...
By default, the option is disabled.

Since it is glycol in the pipes, is it really necessary to activate this option?

Goods.

[Christophe]

Ah, I misunderstood ... it's anything then ...

It is when it is cold and clear that the solar has the most interest!

My remarks on the drainback are still valid;)