negative head pump

[Rich2111]

Hello

I'm fitting a small sink and toilet next to a bedroom in my mum's house, but just need a little advice. The water system is gravity fed with the cylinder in the bathroom on the ground floor. The cold water tank is on the first floor in a loft area behind the cupboard where I want to fit the toilet and sink. Therefore, my question is:
1) Will I need a negative head pump to feed the sink upstairs and can I just spur of the pipework to the sink downstairs and have the pump work both sinks.
2) How close does the pump need to be to the taps as would like to move it as far away as possible to keep the noise down.
3) Can I take the feed straight out of the cold water for the toilet to save the pump coming on when the toilet is flushed and maybe even the cold to the sink?

Regards Rich

 

[Rich2111]

Will I also need to fir a Surrey Flange to the cylinder?

 

[ALCPlumbing]

You will need a negative head pump if the outlet is higher than the cold water storage tank's water level.
If you are only wanting to pump a couple of outlets as opposed to the whole house you will need to run dedicated feeds to them from the pump and the pump should have its own feeds from the tank and from the hot water cylinder.
Yes you will need a Surrey flange to ensure you don't get air in the pump or you can run the pipework in such a way that all the air will escape up the vent pipe. This is usually explained fully in the installation instructions with the pump.
Get a Stuart turner pump for quality and reliability and if it is to feed multiple outlets go for one in their monsoon range as they have 22mm inlets and outlets so provide good flow as well as pressure.

 

[Rich2111]

Thanks for reply, just realised that I can come off the mains for the toilet and cold for the sink as the mains runs to the tank next to the cupboard. Gonna tee off the hot directly below and see what flow I get at sink height. Sink is only being used to wash hands after using the toilet and is only going to be used a few weeks a year when my mum has friends and family staying so doesn't need to be great.

Regards Rich

 

[Rich2111]

There is also a header tank that is in the top of the loft about a meter above sink height, will that help with the hot water flow rate from the cylinder?