Intermittent pressure of hot water from pump

[Hannah73]

Hi,

Forget I'm female, just help me out, guys, much appreciated!
I've got a diagnostic query- Gravity hot water system to a pump for upstairs hot water only. The owner reports intermittent fluctuations in pressure. There are no changes in pump noise when this happens. We thought it could be a foreign object that keeps blocking up at a certain bend or slight narrowing in the pipework. Flushing the hot feed from the cylinder to the pump hasn't worked, no visual signs inside the cylinder either. The pump seems to work straight away and continues when water on. Next thing is to change pipework from the cylinder to the pump which is now copper with a few 90 deg elbows. If no joy, thinking about perhaps the cold feed pipe. Any suggestions??

[newbie1]

bit confused here gravity hot water thats fed to a pump??please dont get me wrong are you refering to the central heating pump?can you explain the system in a bit more detail

[Puddle]

Is the hot supply pipework to pump direct from cylinder and connected to cylinder by surrey or essex flange,if not what is head betwwen cylinder and tank,what make of pump is it
Ps why should we forget you are a female,lots of good female plumbers :-)

[Plumbstar Tom]

I'd also check the NRV's on the shower, assuming it is connected to a shower

[heinz57]

Is it a shower pump youre on about? Try checking the filters at the pump, they may
be blocked slightly or there may be a filter in the shower unit that requires a
good clean or maybe the shower head itself is a bit scaled up. Or as Plumbstar Tom
suggested the NRV's.

[Hannah73]

shower pump! It also feeds the hot water taps upstairs too-sorry not clear!

[Plumbstar Tom]

Hi

Technically a shower pump should not boost taps as its designed for showers only. Ceramic disc taps cause problems with pumps in creating pressure waves. Do we have the connection yet? Surrey Essex? etc

[Hannah73]

Hi, it's an Essex- off the side connection- correct county of choice?! I think this also feeds the rest of the upstairs taps-bath/ 2 basins too- they also have intermittent pressure fluctuations. Could these extra branches to taps be a cause? Maybe the shower pump can't cope-only supposed to be for the shower as one of you said? I'll find out the make. Ta for suggestions so far!