Shower pump is causing intermittent pressure problems

[thehenster]

Hi all,

I've tried to draw a (tragic) diagram of what our bathroom looks like and where the pump is: https://www.dropbox.com/s/bjhoupjanm49u07/SCN_0002.jpg

I believe the pump is a positive head pump.. and sometimes to get the shower going you need to turn on the bath tap too. That gets the pump going and then you can have your shower. Not ideal but workable.

But... quite often the cold tap in the sink and the toilet cistern have very low pressure. Just a dribble out of the tap and the cistern takes ages to fill. Bizarrely, what boosts the pressure is running the cold tap in the bath, kicking in the pump, and then turning it off! While the pump is running the pressure in the sink and toilet is zero.. but then the pump is stopped it somehow frees things up and the cold starts running into the sink and toilet.

I know I could replace the postive head pump with a negative head pump, and I probably wouldn't have to use the bath tap trick to get the shower running. But that wouldn't have an affect on the sink and toilet should it? They're before the pump?

What is this madness?

 

[AngelesPlumbing]

The way you say i guess starvation of water and low pressure in the mains. Do you live at top floor flat? If yes, you need a cold water tank feed to shower and bath if you have space in the ceiling, if im wrong call a professional

 

[picasso]

The pump is creating an airlock in the pipes to the basin and toilet, pumps are supposed to have dedicated for this reason, I dont think you can do much about it other than replumbing the pump properly.