Hi Guys

need some advise please

So i have a 3.2kw heat pump heating my 200L geyser to 60 degrees( between 9am and 4pm), all from PV. Problem is  after the evening shower, the geyser water is cold in the morning, and i have to run the heat pump again for many hours to get hot water.

Im thinking of adding another 200L geyser in series and it be heated  by the heat pump ( I know the heat pump is too small and will take many hours, but thats ok, as its PV power).

Question is, by having 400L of hot water (60 degrees) , and with 5 of us at home, do u think that this will address my issue of having no hot water in the morning?

All my shower heads are 5lpm and max shower time is 8 mins per person, and 2 showers per person a day..

So the goal is to run the heat pump once a day and have enough water for evening and next morning showers, before the heat pump needs to run again..

Alos dont want to throw another 20k+ for a bigger heat pump at this stage..

 

thanks all

You'll definitely be better off if you can heat 400L vs 200L to 60°C. You'll just have to check you've got capacity on your heat pump - although at 3.2kw I imagine you do. A quick google confirms this, roughly 16.3kwh or 2.3kw of heating for 7 hours to get 400L from 25°C to 60°C.

Worth checking the insulation on your geysers as well to retain as much heat as possible. My geysers lose between 0.5-1°C per hour depending on temperature. Was closer to 1.5°C per hour without extra insulation.

yeah i do have capacity on the HP, as it currently takes about 2.5 hrs to heat the 200L, so based on this logic, 6 to 7 hrs on 400L...

 

I bought a house with twin geysers in series. A heatpump heats by reverse direction circulation. I added a Geyserwise DC solar to the second (outlets to the house) geyser.

I monitor&plot all pipe temperatures in/out of geysers. Some interesting graphs.

I am now considering adding a solar powered circulation pump to push hot water back from the second geyser to the first geyser (but only when the second geyser has reached 45Celsius), and off course when the solar GeyserWise is heating. This means that, when I shower in the evening, the first geyser will feed semi-heated water into the second geyser, instead of super cold water. This means I can run both geysers on 45C, instead of on 60C, so the heat lost during the night is less.

comments ?