Thermostat shower mixer

[Mick67]

Hi all
i just fitted a new shower mixer and getting very little water coming out of the shower head .
when it’s first turned on no water comes out for about 30 second then it will flow but very slow .
if I remove the mixer valve/taps and then turn the stop valves on water flow straight away and with better flow?
any suggestions before I fit a pump .
thanks .

 

[Deleted member 120897]

So I’m guessing it’s an open vented system? What’s the distance between shower head and base of the cold water storage cistern? What’s the minimum working pressure of the shower?

 

[Mick67]

So I’m guessing it’s an open vented system? What’s the distance between shower head and base of the cold water storage cistern? What’s the minimum working pressure of the shower?

Hi Chris
yes it's an open vent system.

 

[Mick67]

So I’m guessing it’s an open vented system? What’s the distance between shower head and base of the cold water storage cistern? What’s the minimum working pressure of the shower?

Sorry reply is in small parts as it won't let me post all of it .
The working pressure is 0.3 and it about one meter from the tank

 

[Mick67]

I'm guess your going to tell me that's where my problem is

 

[Deleted member 120897]

Sorry reply is in small parts as it won't let me post all of it .
The working pressure is 0.3 and it about one meter from the tank

I'm guess your going to tell me that's where my problem is

Sounds likely, as 10m head (distance of base of cistern to head) is approx 1 bar pressure, so 1m = approx 0.1 bar.