Ideally, as close to the solar panel as possible — to limit heat losses.

You will need to identify a route for the hot water pipes to get from the solar system down to your household plumbing. Your plumber may advise on the best way to do this.

If the distance between solar panel and hot water cylinder is greater than 12 metres, then it may be necessary to purchase an optional larger (3 speed) pump.

Think of the circulating pump like your heart. It is very small and operates on very low power (14 watts). And it is inaudible.

The pump will only switch on intermittently when there is hot water to deliver to the cylinder. It does not operate at other times, including at night. You can forget it is there.