The pressure in our house upstairs is not good enough. This is despite having a more than adequately powered Hitachi pump downstairs. What we lack is a large tank connected to the pump (mrs does not like) Would a tank improved the water pressure or make no difference?

Yes it would improve the water pressure adding a tank as would installing a second pump on the upper level if it's a long way up from the initial pump.

My tank fed pump is adequate to feed the whole house,four bedrooms and bath rooms as well as sinks,washing machines etc,although obviously there is only a number of outlets open at any one time.

I assume you are pumping direct from the mains (unwise and illegal).

If the incoming supply is very low pressure/flow then adding a small tank (even 200L) would make a difference and would also bridge over any water cuts you may have.

You should do something like this:-

Using a storage tank may or may not allow your pump to pump better...put out more pressure. If the water pressure from the soi main is too low it will have an impact...how much is too low I couldn't say.

I can say I have my setup where I can pump from my storage tank (which I do 99.9% of the time), direct from the soi main, or from both at the same time. My soi main pressure here in western Bangkok runs around 8 to 10 psi...many times lower. During times when I did suck directly from the soi main during some storage tank maintenance and when I had the tank completely disconnected for a few days, I noticed no difference in pump pressure to the first story or second story of my home. Your results may vary.

It may not be an an input water pressure/volume issue; maybe your pump has an issue in it's pressure setting.

And when you say more than adequate power, what model is it, what wattage, what water pressure is it suppose to put out, etc? "Usually" if the pump is rated at about 200 watts it will put out 2.1 to 2.8 bars of pressure (give or take a little), but under 200 watts it's usually around 1.3 to 1.9 bars. The later size pump probably would have lower than desired pressure in a two story house....but it all depends on what a person considers adequate pressure. For my house I use a Mitsubishi 250 watts, 2.1 to 2.8 bar pump.

thanks for the replies esp diagram now just have to convince mrs think ours is 250 w

thanks for the replies esp diagram now just have to convince mrs think ours is 250 w

If your wife's objection is to the appearance of the tank, you can have an underground tank.

thanks for the replies esp diagram now just have to convince mrs think ours is 250 w

If your wife's objection is to the appearance of the tank, you can have an underground tank.

Plus the plastic type tanks can be bought with all kinds of female designs like flowers, birds, animals, different colors, etc.