Lost pressure on shower

[jiffter]

Hi,
Installed a power shower using a techflow QT120-2 pump at 2.7 bar about six months ago.Noticed last week that the pressure from the shower head was greatlly reduced so tried the other two sprays on the shower and they were also reduced in water pressure.I've also noticed a rumbling or vibration sound coming from the shower pipe work in the loft (plastic push fit) so i've tried cushioning it on felt without success.I'm baffled as to why i've lost the pressure and don't know where to go from here.
As always, this forum has never let me down with any problems i've posted, always sorted,always fixed.Please help!!!!

 

[sooey]

Check the easy things first,take the head off the shower hose and see if water comes through alright, if not take the hose off the shower body and see if that discharges. Could be blocked sprayhead or twisted inner hose.

 

[jiffter]

I've taken the shower head off and doesn't seem blocked,also looked at the hose and bar and the jets on the shower and they all seem clear.The main shower head doesn't use a hose,just pipe work that connects to the main mixer part of the shower. The hot water supply comes from a techflange i fitted into the hot cylinder and the cold water supply from a mains pipe already there from the previous electric shower.

 

[sime10]

Mains cold water mixed with gravity fed hot water????????

 

[jiffter]

My mistake, heads up my posterior today. Cold water feed from water tank in loft.

 

[sime10]

Ok so its tank fed mains are there any filters on the inlet pipes to the pump or shower mixer?
And I take it the pipes rise from the airing cupboard (just a guess) then back down to the shower?
Are there any air vents in the loft?

 

[seco services]

check your pump filters

 

[jiffter]

The pipes rise from the airing cupboard as you said then back down to the shower.The pump filters look completely clear but will have to dismantle the shower to check those filters.Don't quite now what you mean by air vents in the loft, there are brick vents in the loft (ami being stupid)?

 

[sime10]

On the manufacturers instructions it will say that if you are rising to the loft and then back down to the shower you will need airvents on the highest part of the installation on the pipes to dispell any air that can get trapped even tho its pumped.

 

[jiffter]

Okay, no i feel a total lemon for answering the question about the air vent.
There are no air vents on the pipe work in the loft so if i go to the plumers merchant tomorrow,what do i actually ask for and are they used on the hot and cold pipes?

 

[sime10]

http://www.screwfix.com/prods/19155/Plumbing/End-Feed-Fittings/Air-Vent-Cap-End-Feed-15mm

But if you cannot solder you will have problems, I don't know about any plastic vents or compression.

 

[seco services]

bes stock compression vents or any plumbers merchants.

 

[seco services]

bes stock compression vents or any plumbers merchants.

 

[sime10]

Ok you maybe right but never had the reason to use one so never relly looked till now.
I have made them up using female Iron to copper then used a vent into the 1/2"

 

[jiffter]

Many many thanks to everybody's help on this subject;at least i've something to go on now.
Much appreciated.