Cold water tank mystery leak, then dropping through the ceiling.

[saveasteading]

There is a leak from a big cold tank in the attic. It is all up on a gantry to maximise head, and very difficult to access.

 

I can't definitely see the source, as it spreads over the ply deck, and seems even to be a couple of areas.

 

I can't see any leaks from connections.

 

Annoyingly the drips appear to slow and stop when I am observing....that might be some clue.

 

What I have see is a dribble from the metal strengthening strap.  Plus I think I saw a drip from further along that moulding.

Do tanks fail?

 

The tank was not full. I perhaps have to stop all household use and check overflows. ( I previously found that the adjacent hot header overflow had never been sealed. Same plumber 30 years ago).

 The overflow pipes are pointed down into the water. Is that an intentional thing?

 

Photos. 1.The small tank in front is the hot water header. Behind are 2 large cold tanks, linked....one shared float valve, each with an overflow.

 

2. The linkage between the 2 tanks and the metal strap. Dribble stain visible on the right tank.

[marshian]

Whole load of pain in that picture - my sympathies.

 

You haven't fitted a water softener in the last 12 mths have you?

 

I had a similar experience with my cold water store tank when I fitted one - the softened water removed some limescale that had clearly built up over a while sealing up a leak

[Nickfromwales]

8 hours ago, saveasteading said:

The overflow pipes are pointed down into the water. Is that an intentional thing?

Yup. An age old thing, so if they start spitting water out it doesn't go all over the attic.

 

As for the leak, these do flex and move about, and if they've been in for 30 years you've had "value for money" lol.

 

Given the amount of water, and where these are, I'd put my hand in my pocket and get them both replaced immediately / local plumbing refreshed. Then enjoy another 30 years. In my experience, disturbing one and leaving the other often causes the other to leak. I think it's a pact that these things have, written in ancient transcripts by aliens who visited from far away, because old plumbing stuff just seems to hate to be interfered with.

 

By the time you've got the plumber there changing the 1st tank, you're not looking at too much more to get it all up to scratch and all nice and new.

[saveasteading]

5 hours ago, marshian said:

haven't fitted a water softener

No.

 

5 hours ago, Nickfromwales said:

these do flex and move about

And crack?   It's in the dark, presumably made for the job, and feels flexible still.

 

5 hours ago, Nickfromwales said:

you've had "value for money"

 

It would be a lot of work, especially as my improved loft ladder (one that doesn't disappear under me), restricts access for part sizes.

 

I may check again whether there is any problem when the tank is full. Perhaps a leak from the overflow.It occurs to me that this may have been dribbling for a very long time.  I had the other tank leak, sorted it, and didn't look again. Maybe this was always adding to it.

It hasn't come through the ceiling in that  time, but i think it may have mostly evaporated until yesterday..for who knows what reason.

Today it is tamed, i've used a hitech system of a bucket under the dripping point, a hole in the ply deck and a string to encourage it to that hole.

No ordinary string though.... a piece of fibre optic cable....that's the hitech bit.

 

What is the pressure relief  pipe for? the one that loops over the tank. I know what hey do in hot tanks, spluttering and splashing hot water. Is it the same for cold but more as a precaution than ever really spitting water?

 

As a precaution I could bend the float valve down a tad. Does anyone have  a clever method of doing that in situ?

[saveasteading]

Eureka.

 

The overflow is leaking as I latterly suspected. Then some of it runs along the angle strengthener to where the photo shows, confusing the issue.

 

So the tank is filling and the inlet is dripping overnight...dry in the day when I have looked before.

 

 

Access isn't easy but about to venture in.

 

Plan A I think will be to convert all to mains and throw these tanks out.  That will be a proper plumber.  Only a few appliances run from these tanks.... 2 x wc, and one of our 2 hot water tanks.

 

 

[sharpener]

On 17/03/2025 at 14:12, saveasteading said:

Eureka

 

You have been lucky! I read the title as the whole tank dropping through the ceiling.

 

Yes if you can convert to mains pressure and ditch the 30 y/o tanks you will feel all the better for it. Make sure first you know where the vent pipe comes from and how you will deal with it.