Save gas - optimize control?

Do I understand correctly… Your storage tank has also provided heating water in the summer (heated by gas), although no heating was needed? My problem is that the hot water (when we draw it) is reheated by the burner, even though the solar collectors indicate over 100 degrees.

No, it is more that the control itself decides when heating is necessary. As it is now, it is not allowed to do that, but I have set it so that it does not turn on. What you describe would be more like prioritization in my case. Our solar thermal system is set up so that heat is already dissipated below 100 degrees to prevent the installed parts from getting too much damage. Dissipated means I also pay for the electricity used to flush away the hot water.

The answer from Wolf is here, it reads: From a distance, unfortunately, we cannot determine whether there is any potential for savings. It would be possible for the factory service to inspect the system through an adjustment service which is billed as a service at 219.- plus VAT and adjust and explain it to you according to your wishes. To commission this, we ask you to use this link (link). The gas boiler will be set so that when no solar input is active, comfort is maintained. Otherwise, it cannot be guaranteed that you will reach the desired temperature. When the solar control is connected to the heating device, there is a solar boiler stop that heats the hot water preparation only to the minimum hot water temperature after a successful solar charge on the following day until 2 p.m., and that is the factory setting of 45°. After that, heating resumes according to the basic settings. If it is sunny for longer, you could set the hot water preparation to standby and would then need to intervene manually, for example with a one-time loading. (Here follows an excerpt from the operating instructions). We cannot make any statements about the heating operation from a distance. I have removed individual spelling errors. Best regards Gabriele

You could set the hot water preparation to standby if it is sunny for a longer period

Dear Gabriele, have you found the standby button for hot water? I think that would also stop the legionella heating, right?

Hello Yvonne, yes, I simply turned off the gas manually. The hot water has not run out since then. It feels hotter to me than before.

Legionella in a two-person bungalow don’t really worry me. I know stagnation areas and legionella professionally from multi-family houses, preferably with old rusty pipes, apartments far away from the boiler, water taps that no one turns on for several weeks, clogged aerators. None of that applies to our house.

I will allow the gas as long as we either start to feel cold or have to wash our hair too cold a few times. And who knows for what other reason.

We are very privileged here with single-family houses, not least because we can decide on our own even if there are no patent solutions.

Here is my experience with our Wolf gas boiler (with solar module). For weeks/months we had the feeling that the solar heat was not reaching the boiler. Finally, our plumber was here.. He completely flushed the solar line. It also turned out that air bubbles were blocking the circulation.. so nothing could get through. Now it finally runs the way we imagined.. The solar boiler heats up properly (sometimes up to 70 degrees).. A mixer mixes it down to 50 degrees when drawing off. And since then the gas boiler has not switched on anymore! I also asked him if we could simply turn off the gas.. Basically yes.. but an error appears on the display that would have to be "acknowledged". He rather advised us against it. Is it the same with you ?