Water tank leak! Help!

[Diynoob1989]

Hi all. I'm new here so first of all hello.
I have a problem with my water tank. I know nothing about plumbing so please bear with me. The tank I am referring to is a large black tank that is next to a smaller tank which I assume is to do with heating. The large tank has a ball float in it.
Anyway...
Recently I boug a new hose to water the garden with. My problem starts here. I watered the garden for around 20 mins and at around 3am the next morning I was woken by dripping. I went into the loft and found that one of the overflow pipes had disconnected. I reattached it and voila.
Today I was watering again and after maybe thirt minutes I heard a lot of dripping. I went in to the loft and the large water tank was literally overflowing. It was leaking out of the top of the tank. I threw down towels and ran the cold water taps but the water level didn't go down, I ran the downstairs hot top and the level went down, I am very confused. The water tank if full of cold water by the way.
My question is, a) what is the problem and b) does my new hose have anything to do with this? This is the first time ive ever had a problem like this so it's quite coincidental,

Thanks for any help

 

[FiremanT]

Hi all. I'm new here so first of all hello.
I have a problem with my water tank. I know nothing about plumbing so please bear with me. The tank I am referring to is a large black tank that is next to a smaller tank which I assume is to do with heating. The large tank has a ball float in it.
Anyway...
Recently I boug a new hose to water the garden with. My problem starts here. I watered the garden for around 20 mins and at around 3am the next morning I was woken by dripping. I went into the loft and found that one of the overflow pipes had disconnected. I reattached it and voila.
Today I was watering again and after maybe thirt minutes I heard a lot of dripping. I went in to the loft and the large water tank was literally overflowing. It was leaking out of the top of the tank. I threw down towels and ran the cold water taps but the water level didn't go down, I ran the downstairs hot top and the level went down, I am very confused. The water tank if full of cold water by the way.
My question is, a) what is the problem and b) does my new hose have anything to do with this? This is the first time ive ever had a problem like this so it's quite coincidental,

Thanks for any help

answers:

a) Faulty ball valve & possibly undersized / restricted overflow

b) No

The cold water in the loft is heated in your cylinder, so will come out of the hot taps. Some homes do have some cold taps running off the CWS as well, but if the level did not drop when running a cold tap, it is plumbed off the mains

 

[Diynoob1989]

Thank you. So is there any reason why is has just started and only happened after using my hosepipe? What makes the tank overflow? Am I ok to go to bed and not fear for my house being flooded? Lol

 

[ALCPlumbing]

As you have no DIY plumbing experience I would advise you to call a local plumber. As FiremanT explained it is most likely the ball valve is in need of a little TLC. Probably just needs a new washer. Also ask the plumber to check the overflow. It's a little worrying that all the excess water didn't escape down the overflow and outside.

 

[ALCPlumbing]

There should be a stopcock on the mains feeding the tank. This can be found by tracing the pipe that is attached to the ball float valve. You could shut it off overnight. If it's only feeding your cylinder it's unlikely you'll need the tanks volume of water by the morning.

 

[stardanny]

How is the hose connected to? Bib tap? Kitchen mixer tap?

Daniel.

 

[Diynoob1989]

It was connected to the bath tap the first time and then to a mixer tap the second time, I've only had a problem after using the hose. Strange.

 

[Diynoob1989]

Actually I've just realised it didn't happen when I used the bath tap. It was when I used the mixer tap downstairs both times. It was fine when I used the bath tap

 

[stardanny]

Ahh, thought so, back feeding from kitchen tap to tank via hot water..

What happen is when you turn on cold tap on your mixer, somehow a hot tap also open as well and the pressure on cold water is forcing hot water back to the cold water tank via cold feed or vent pipe and start filling tank to overflow.

When using hose, make sure hot tap is shut off or better, fit a outside tap.

Also, you might want to check the overflow pipe is not blocked.

Daniel.