Water tank not filling up

[flarkey]

i am having issues with my water tank at my apartment. The water tank is not filling up so the stop-cock is always open and constantly letting a trickle of water flow into the tank. I was up in the roofspace last night trying to sort things out but i didnt want to start playing around with valves and taps, cos I'm terrible when it comes to fixing things.

the system is shown below. When I close lower tap the water flow stops. When I close the taps near the tank the flow continues but the supply to the house does off, as you would expect.

I'm not sure what to do.....

Ps. I think there should maybe be a second supply pipe shown. In the imersion heater closet there are two pipes labelled "vent" and "riser", and then the tank supply and cold water supply.

Thanks for your help.

 

[corgiman]

nice pic

change the ballvalve

 

[JohnD]

Let me check... water is going into the tank, but it is not filling up? It isn't reaching the overflow pipe and runnng out near the top? Are you completely sure about that?

If you close the lower tap, and wait, does the water level in the tank drop?


The only way you can keep pouring water into a tank, or a bucket, and not have it fill up, is if it's running out somewhere.

So either you have a tap running in the house, or e.g. a lavatory cistern overflowing, or you have a leak.

Turn off the supply to the hot cylinder, and the supply to the cold taps, and see if that stops the leak.

If it does, turn them on one at a time to determine if you have a cold leak or a hot leak.

It's quite likely to be a WC cistern with a ballcock that needs changing.

 

[jobloggs]

If its not a toilet cistern overflowing as suggested by JohnD, but a leak in the hot system you sure would notice the flood unless its below ground floor level and can escape into ground.

Flarkey. How did you insert picture directly into post. I assume it is a drawing created in Word?

 

[jobloggs]

Flarkey. Just noticed you said the water was trickling in. You have a ballcock problem here as the flow shoud be quite strong when the ball is hanging above water level.