Hi
The cistern for our loo fills very slowly. I believe it is mains fed, looking at where the pipework comes from. I took the old valve apart to check for debris etc, but it was clear. The higher flow (red) insert was in the valve. With the ballcock attachment detached from the inlet I carefully turned the water supply back on and there is a very strong flow, the cistern filling in under 30 seconds.
With everything reassembled, the fill time was back to about 5 minutes.
So, I bought a replacement cistern fill valve. I have just installed it and the fill speed has not improved at all. Again, if I take the top off the inlet there is a very strong flow of water.
I assume I am missing something obvious. If someone could point me in the right direction that would be awesome!