DIY Doctor UK DIY Forums

We have just had a Salamander CT55 xtra 1.5 bar pump (positive head) fitted to power our Mira Atom mixer shower which we just had installed and previously had no water pressure to it at all. The shower is now working but the pump switches on and off constantly so there's 1 second of water followed by 3 seconds of no water.
We ordered and fitted a non return valve to see if that would resolve it but it hasn't. We are at our wits end as everything we have bought and had fitted has been on the recommendation of plumbers.
We have a gravity fed system with a cold tank in the loft and a hot water cylinder in the airing cupboard, where the pump is fitted next to.
Any suggestions as to what could be causing this and how we could fix it would be greatly appreciated. Many thanks!

have you got a surrey flange fitted in the top of your hot water cylinder

Hi lets have a look, thanks for replying. No we don't have a Surrey flange, just a copper pipe coming from the tank.
Thanks

Hi let's have a look, thanks for replying. We don't have a Surrey flange fitted, just a copper pipe coming from the top of the tank.
Thanks.

Hi, the best system for a pump is separate h&c supplies,cold water supply from the roof tank and a surrey flange giving a separate hot water supply,then the pump is taking water without being starved by other appliances using water,
a way to test the pump is take it out and put the pipes in a container full of water and see if you have a constant flow