Slow filling of upstairs toilet and slow running water from upstairs basin mixer tap

2 Aug 2007
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United Kingdom
Hi all,

I have a two story house with loft.

In the loft I have a cold water tank and in the first floor airing cupboard I have a hot water cylinder.

Out of the lower side of the cold water tank there is a horizontal pipe which is of around 1969 vintage which after running horizontally across the loft then has an elbow which takes the pipe vertically down through the airing cupboard.

Under the floorboards of the airing cupboard the pipe has an elbow which takes the pipe horizontally where it splits. One of the splits then rises vertically through a reducer from the 1969 vintage pipe into 15mm pipe where it terminates in a brass fitting and then has a flexible pipe to feed a basin mixer tap, the other split then continues horizontally where it too goes through a reducer and from the 1969 vintage pipe into a 15mm pipe where it terminates on a brass fitting and then via a flexible pipe feeds the upstairs toilet.

Both the upstairs toilet and the basin mixer tap run slowly. They both run slower than the hot water from the basin mixer tap.

I would appreciate any thoughts on what might be causing this slow running of cold water only.

Many thanks

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So after isolating the water, I removed the flexible pipe that feeds the basin mixer tap from the brass fitting leaving the flexible pipe connected to the basin mixer tap. I then very quickly fitted an alternative flexible hose and restarted the water into a bucket. This resulted in an increase of water flow and no expulsion of air into the bucket. I then reconnected the original flexible pipe to the brass fitting which resulted in a cold water flow from the basin mixer tap that is identical to the hot water flow.

The toilet is still slow to fill though. The toilet is a 12 year old B&Q item.......
Do the same to the WC. And check the float valve for an inlet filter that may need cleaning .
thanks Terry very greatly appreciated. Just out of interest, do you think the above could have been caused by an air bubble before the part where the pipe splits????
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Unless you have drained the loft tank ,or at least it's water level dropped below the outlet levels ,it's unlikely for air to have entered the Pipework.
Quite possibly an air lock then. Was flow better before draining loft tank , went slow immediately after ?
Air or detritus pulled down into the pipework and blocking outlets at filters/Indices.
ok thanks people gives me something to consider / act upon. If as suspected it could be an air bubble can this be solved by pushing water up through the tap using perhaps a garden hose with a fitting on the tap?
Sometimes yes. While you're playing with the flexis, make sure they are either straight or running in smooth curves- both will help your flow issues. Flow would probably improve if you ditched the flexis and replaced with tube (placcie 15mm and speedfit fittings are pretty straightforward if you don't fancy soldering)
ok many thanks people greatly appreciated for your time and efforts

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