Airlock in cold water pipes?

11 Sep 2007
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United Kingdom
Hi Guys,

Full drain down of CWS and HW Cylinder, on filling back up the hot and cold was nothing but a dribble. System is standard HW cylinder, vented. Cold to bathroom feeding of tank in loft.

Managed to blow the airlock out and sort the hot out, by connecting the cold to hot at the washing machine point. The cold is still a problem. Cant seem to shift the problem.

Could it be a blockage or airlock?

Cold water tank seems to be quite new with not much c*** in it so dont think limescale lumps etc have blocked the pipes.......

When the taps are left off for a few minutes, the pressure does build and when turned on flows for about 30 seconds, then down to a dribble, then to nothing!

any advice welcomed!!
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get a hose onto the cold tap in the bathroom and force it up so thewater goes back up into the tank and clears the airlock or in the loft get a bit of hose and feed it into the cold pipe so you will need a t shirt on so you dont get wet and just push it in the hole and put the hose on to were the water comes out the ball valve and press the ballvalve down or just turn your hot on so it emptys itself and leave your cold open in the bath and let it blow it through
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make sure you put it down the cold and not the hot .should have gate valves on turn one off until you know which is which.then carry on.

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