ᐅ Air-to-Water Heat Pump: Current Consumption and Data

When I say "my," I mean it personally. Once the pipe is installed, it should be flushed once a day. But 5 minutes each time is enough.

That is also my current thought/approach.

KingJulien schrieb:

Are you saying that having no circulation at all is more hygienic than running it occasionally?

For reasons of efficiency and "I-don't-need-it," I would gladly leave it off completely.

It might still depend a bit on the specific piping details.
Basically, Legionella bacteria thrive best at temperatures between 25-45°C (77-113°F).
That’s exactly the temperature range circulation can create.
Additionally, circulation can spread any existing Legionella throughout the entire system.

Therefore, it’s best not to install circulation at all. However, if it’s already present, there might be cases where otherwise some parts of the system become “dead legs” that never get fresh water. Even then, all the arguments mentioned above still apply. ;-)

I just realized there are other issues like Legionella bacteria. I prefer to run the water once a day; the basic instinct demands flowing water 😉 It’s also good for triggering water treatment.

driver55 schrieb:

A look into the manual might solve the puzzle…

Unfortunately, I couldn’t find anything about that.
By the way, the regulation states that when using an air-to-water heat pump, a domestic hot water temperature of 50°C (122°F) is sufficient for Legionella protection.
I set it to 50°C (122°F) with an 8K (14.4°F) hysteresis, so it only heats the water once per day. For that, I turn off the domestic hot water circulation.

There is always the argument here that you would then need to thoroughly flush all outlets during the legionella prevention program. Otherwise, you might end up cultivating heat-resistant bacteria.