Nagative head kits

[trev Thane]

Hi all,
pleased to meet you🙂,
i have a query regarding negative head kits, do they contain flow switches as i have a customer who wishes me to install a standard circulator to pump grey water from cwst to a wc cistern on the the next floor up and i,m not sure wether to advise my client to buy a single impeller pump incorporating a flow switch or purchase the pull cord type?

Many Thanks for your time,

Trev,
Plumbers Direct.

 

[Dan]

Welcome to Plumbing Forum | Plumbing Advice | Plumbers Forums | A forum for plumbers advice in the UK!

Hello trev Thane, welcome aboard www.UKPlumbersForums.co.uk. Stick around, I'm sure you'll like the place. 🙂

 

[Blackcatgas]

There is a pressurised canister on the pump, when you turn on the power to the pump it will run for a few seconds this presurises the canister, then when you open the tap the pressure is released from the canister and forces the water up hill out of the pipe, this then operates the flow switch and the pump runs, when you turn off the tap the pump run s on for a few seconds represurising the canister and its ready to go again.

I really ought to learn how to spell pressure/ pressurised.

 

[WHPES]

They are pretty much the same as a standard pump with flow switches but an artificial head is held by the pressure vessel in order to get the initial pressure drop and flow to switch the pump on when the shower valve is opened. Therefore you can work a shower with a low head or above the water cistern such as in a loft conversion.