You need a separate heater that heats the water as it's used and the plumbing would be 3/4 all around, the main has more than enough pressure for that.

[+] the_post_of_tom_joad@sh.itjust.works 2 points 2 years ago* (last edited 6 months ago) (1 children)

[deleted]

[–] SHITPOSTING_ACCOUNT@feddit.de 2 points 2 years ago (1 children)

Water typically comes in at around 15 degree Celsius, so it needs to be heated by around 25 degrees to feel warm.

A regular high flow shower head flows up to 20 liters per minute (that's 5.3 gpm in American). That's 500 kcal/min of energy that needs to be added, which is 35 kW, or a total of almost 150A at 240V.

[–] Kecessa@sh.itjust.works 1 points 2 years ago (1 children)

You would use a gas water heater for that since they heat the water much quicker...

I used to live in a 200 units building with a central heater for all the hot water and we never ran out and the water was hot as fuck, just need to use the appropriate material for the job 👍

[–] SHITPOSTING_ACCOUNT@feddit.de 1 points 2 years ago

Indeed.

I guess you could also use an oversized heat pump in theory. With a setup like this, recirculation and/or wastewater heat recuperation would also need to be looked into. Either would significantly reduce the cost of running this.

But purely resistive heating without any form of recuperation would need impractical amounts of power.