Low water pressure/no water at all from bleed valve

[dirty harry]

Can anyone explain this? I tried bleeding a cold rad this morning (expecting there to be air in the system) but when I opened the bleed valve only a trickle of water came out (no air). So I closed the lockshield valve expecting the water pressure to increase, but instead the water stopped completely! However, when I closed the TRV and opened the lockshield valve, water starts coming out of the bleed valve!

This is an upstairs rad near the airing cupboard/pump and in the past has always heated up quickly along with the other upstairs rads. Also, I had a new pump fitted a few months ago so I know that's ok.

I also have another downstairs rad that has stopped working for no reason at all. Could this be connected to the problem upstairs?
It's a microbore system by the way.

Any clues anyone? Cheers.

 

[tryitandsee]

Perhaps when the pump was changed crud entered the system from the f&e tank and is blocking the flow manifold to the rads.

 

[lifesagasman]

a radiator doesn't stop working for no reason. there will be a reason....see above post

 

[dirty harry]

Perhaps when the pump was changed crud entered the system from the f&e tank and is blocking the flow manifold to the rads.

Does that mean accessing the manifold to unblock it? Or might flushing the system clear it?

 

[gas_man_gaz]

from what you have said id check the trv isn't jammed in the close position before jumping in