I found that my water company was reducing the water pressure to save wastage from leakes
it appers to run below One Bar pressure untill the morning peak has past even then the increase is minimal but seems just enough for me to have a shower without temp. fluctuations,I have a 10 kw. shower
You may have to goto a lower one say an 8 kw. to cope with the lower pressure if that is the problem
I suggest that you speak to your water company to find out what the pressure is in the system in your area
hope this helps
superscot, January 2011
