Disable hot water circulation?

Hello dear forum,

what are the opinions on the topic of hot water circulation? We have a 145m2 house with a Vaillant compact system (Auro Compact VSC S 206) including solar. The hot water preparation is active from Monday to Sunday from 05:40 - 22:00 hours - circulation from 06:00-22:00 hours.

To save energy, I would prefer to activate the hot water preparation and the circulation only at times when we really need hot water. For example:

06:00 - 08:00, 15:00-22:00 hours

Is that possible, or will there be problems with Legionella then?

In a single-family house, it should not be a problem. We also have the circulation off during the day.

06:00 - 08:00, 15:00-22:00 hours

Is that doable, or will you then have problems with legionella?

There are no legionella problems. You only get those if the water stays too long in the tank; circulation doesn’t help with that.

Limiting the hot water demand makes sense. In the evening, consider whether it makes sense to run the heating only until 7 or 8 pm, so that during evening showers/washing the boiler isn’t reheated, but only the next morning.
Turning off hot water demand around midday makes particular sense with solar, as the boiler won’t unnecessarily kick in at every little demand and an hour later the sun would have heated it anyway.

At our house, we have it from 5:30 - 8:30 and 15:00 - 20:00 hours. After that, my wife can still take a bath without the water getting cold; otherwise, the dishwasher starts at 10 pm and takes the rest.

Circulation in a single-family new build can be completely switched off depending on the location of the bathroom and boiler. If everything is stacked or next to each other, the lead times should only be a few seconds. Just test it and then regulate down. Maybe you also have a "self-learning" circulation pump. It remembers your daily rhythm and only starts at the times when hot water is usually used.
With circulation pumps with integrated time and temperature control, be sure to check the electrical connection. DO NOT run it through the heating system control, but connect it to power permanently or, if through the heating, set the output there to permanently on and not time-controlled through the circulation program!

Our circulation pump has a separate power connection and has been on for maybe 5 minutes since moving into the house 2 years ago.

We have no circulation, and live well with it.

our circulation pump has a separate power connection and has been on for maybe 5 minutes since moving into the house 2 years ago.

I wrote: Possibly turn it off completely. But IF it is used, then via the internal time and temperature control, not controlled by the boiler. This usually has no temperature control, so the pump runs during the requested period and not only until the water is warm. Connected pumps also have a program that protects against seizing or similar and run for about 10 seconds every 1-2 hours if they have not been requested for a longer time, depending on the model. In most cases, this alone is enough to comfortably always have warm water.