ᐅ Shower buffer tank

Created on: 16 May 2016 09:00
M
merlin83
Hello everyone,

We have a buffer tank with a capacity of 150 liters (40 gallons) planned, and there will be a total of 3 showers in the building. I would like to be able to run at least 2 of them simultaneously with hot water.

All showers are Raindance overhead rain shower heads with a water flow of about 15 to 17 liters per minute (4 to 4.5 gallons per minute) of mixed water (1 x S300 and 2 x S120).

Hot water is generated by the Cerapurmodul 9000 i model GC9000iWM20/100S23 (maximum nominal heat output for hot water is 30 kW). According to the manufacturer, it should produce up to 15 liters (4 gallons) of hot water per minute.

This all sounds plausible to me. However, since I don’t want to regret it later, it would be great if someone with practical experience could share whether the water actually stays warm when using the showers simultaneously.
M
merlin83
17 May 2016 13:10
K1300S schrieb:
Yes, it seems that the 210-liter (55 gallons) option necessarily includes solar. Since you didn’t plan for that, you’re probably stuck with the 150 liters (40 gallons). From my experience with a 160-liter (42 gallons) storage tank and just one shower, it can get quite tight if someone showers for a long time, so I suspect that 150 liters (40 gallons) with two showers will be even more limited.

Good luck

K1300S

How many liters (gallons) of hot water does your heating system produce per minute?

Best regards,

Manuel
K1300S17 May 2016 13:30
That must have been around 15 liters per minute (4 gallons per minute). I should check the exact value, but as I mentioned, it was only noticeable after showering for a longer time. A ten-minute break was enough to have hot water again.

Good luck

K1300S
M
merlin83
17 May 2016 22:15
I have recently spoken again with a contact at Junkers. Apparently, the model is also installed in three-family houses. I will report back with what the practical experience shows.

If that is not sufficient, another buffer tank will simply be added to the house (that’s how it’s usually done, right?).
One0017 May 2016 23:01
My parents have an 80-liter (21-gallon) storage tank connected to their still perfectly functioning gas heating system from 1986, and with some minor compromises, it even worked for a household of four people with two showers... Of course, 10-minute showers were out of the question, but I have to say it worked well (almost) every time for 20 years.
For my own home today, I obviously wouldn’t want that, but 150 liters (40 gallons) for four people should still be bearable under reasonable conditions, depending on shower habits.