Lets start by saying that i live in Taiwan, and things are a bit different here. The public water works gets the water to your house, but you are resonsible for having water pressure in your house, Although the 1st floors usually have great pressure, as you go up floors the pressure decreases, not to even mention the peek times.
So to solve this issue everyone has a pump and rooftop tank or two. or three.
I my house, which i rent, there is a pump and a tank. however, i have come to beleive that the people who installed it didin't run the pipes correctly.
This is the way it seems. I say seems as most of the pipes are in the concrete walls.
I have come to believe this is the way, because of two reasons. If i leave the pump running the tank will overflow, even with the bobbing valve functioning, as it it obviously just filling from the out of the tank, and if i turn off the pump when the city pressure is low, my tank emptys.
So what i am asking is for you to confirm my belief before i goto the lanlord with demands, of hire an expert outside her knowledge.