Leaky overflow pipe -new ball valve fitted

[victor meldrew]

Hi about a month ago the cold water tank was leaking and my trusty plumber kindly replaced the ball valve which appeared to fixed the problem..... i saw the old one that was removed and it looked a bit crusty!!

was away for 2 weeks and it appears all was still well and no leaky pipe

It has now started leaking again however once i run some water it stops it for a while

The hot water tank has also had its ball valve replaced in the last year

I also get some noises from the ch pump unless i turn it right down(but then the radiators downstairs are cold) dont know if this could be linked

Now i am hopless at DIY but after reading some threads here about lowering the water level i might give that a go


How is this done and is there owt else that can be checked while i cripple myself lurking in a junk laden loft

i have my boiler and controls being serviced shortly by BG as part of homecare package how much would it cost for BG to fix this problem?


Thanks in advance....

 

[powell30]

First, lowering the water level is simple. Turn off cold feed supply at stop cock, drain out some water from CWS tank and bend the float arm a little or undo the nut holding the float itself and lower it down the arm (it mayalready be as low as it can go.....bend the float arm a little if so) Switch on water and note level. Make sure it does lock off ie doesn't contiunue to drip. However, this may not be the problem. Have you had any other work done? Mixer taps? Do you have any? try the above and let us know first.....as for BG...well we need to identify the problem first before anyone could guess at what it would cost to fix

 

[victor meldrew]

powell 30 thanks for your quick reply

yes i had a mixer tap fitted in the bathroom about a year ago .....

How can this have an impact ?

but is seems strange that by fitting the new ballcock it stopped the leak for nearly 8 weeks

If the fault was elsewhere surely it would have manifested itself earlier?

 

[powell30]

You maybe right but lets work it methodically, thats why we need to eliminate the obvious and go from there. Which valve was replaced? The CWS tank supplying the cylinder or the Feed and Expansion tank for your heating system?

 

[victor meldrew]

The ballcock was changed on the hotwater tank as that was leaking through the overflow as well

 

[Goldspoon]

Don't try and bend it if it's a plastic one

 

[victor meldrew]

Done some more analysis and strangely the cold water tank does not leak through the overflow if we dont have the hot water on ???

My hot water tank has an overflow thats fine so what could cause it to leak out the cold tank ?

Thanks again for all your anwsers

 

[buck51]

Air in the system ie air lock expands more than water when heated so pushing water from system back up in to f&e
Check and vent all your rads

 

[JohnD]

Done some more analysis and strangely the cold water tank does not leak through the overflow if we dont have the hot water on ???

you have a hot water cylinder, right?

and have you been heating it with a boiler or an immersion heater?

Is there also a small water tank to supply the boiler and radiators (a Feed and Expansion)?

if you look at both your cold water tank and your F&E, have they both got a well-defined mark at the usual water level, and is the water at this height?

and (a really easy one for you) have you taken the ball-valve off and examined it for grit, dirt or disturbed limescale making it drip?