Cold water not getting to the mixer shower

[Leopack]

I wondering if anyone can help. I have installed a Mira digital shower pump in the loft. The hot water side works and there is a good head of water getting to the pump, however the cold side is not working. There is water in the pipe but there does not seem to be enough pressure to reach the pump. I have followed the manufacturers instructions and made sure that the pump is sited more than a 100mm below the header tank and the header tank is more than 230 ltrs. There is good pressure at the other cold taps fed by the tank. I have checked that there are no stop cocks that are closed and all seem to be working.

Open to other ideas on how I can get this working?

Thanks in advance.

 

[seco services]

Have you checked the cold isn't airlocked ?
check the filter and check valve is ok in the unit.

 

[Leopack]

Thanks for advice, I know how to clear an airlock in the hot side but not the cold feed. How do I do that?

Thanks

 

[seco services]

I take it the cold feed is direct from the cws.
Just hold the pipe over a bucket and let it run to you get a steady flow then close the isolation valve and re connect to the unit.

 

[Leopack]

It is gravity feed from the tank in the loft. There is water in the pip as we have been able to suck it up to the same height as the unit but there is no pressure behind it. As both hot and cold are on a gravity feed I would have thought that they would be the same pressure.

 

[seco services]

There is water in the pip as we have been able to suck it up to the same height as the unit

You shouldn't need to suck it up.
Any open pipe that is below the level of the cws will have a flow.
so you either have a restriction/blockage in the pipe run.

 

[mcmoby69]

Gatevalve sheared off shut maybe?