Leaking Overflow

[calandra]

We have an overflow pipe that is leaking. It comes from an attic tank that looks like it is about 1/2 full of water.

It usually starts leaking when the central heating (heat and/or hot water) come on. It used to stop after a few minutes, but lately, it has kept dripping when the heating is on.

We turned the heating off yesterday to paint a radiator and it has been off ever since. Instead of stopping the drip, it went on all night and now water is coming in through the bedroom wall. We tied the float up last night hoping that would help, but it didn't.

A plumber came out to fix this very problem about 2 years ago, and he did something simple - like put water in or take it out of the tank - I don't remember which. But it was fixed for a while, and has now recurred.

Possibly related symptoms: Black sludge bled from one radiator; and sometimes the cold water at night is kind of white-coloured. Not sure if this relates???

Anyway, I've got a plumber coming around again tomorrow and I'd like to have some idea what to expect (it seems to me it should be cheap to fix, but I'm always unpleasantly surprised). And, incidentally, I might have otherwise tried to fix it myself, but I'm pregnant and one trip inside the crawl space where the tank is was one too many.

Thanks for your help.

 

[75pete]

First lets talk about the cold fresh water that sometimes runs white and cloudy....not a problem expect you get your supply from S&E Surrey.

The small water tank in your loft...the one thats over flowing when you have on the CH. You must identify this as the CH header tank and NOT the cold water tank before adding any inhibitor.
If the ball valve is o/k and not letting by and from what you say it sounds fine, and from the "black sludge" you have found, its possible your system is in need of a flush.
Get the small tank cleaned out. THEN..
Empty the CH system and drain out and at the same time keep filling with fresh water.
Shut all rads then open the first of the upstairs one and continue flushing.
Now shut first and open second etc.
Once all flushed and cleaned, top up system and add inhibitor / sludge remover.
This is a simple diy job..........except i see you are expecting
All the best..pete

 

[calandra]

Well, the plumber came out and changed the ball valve in the CH header tank. It was working when he left, but of course, this evening now that he's gone, the water started dripping again.

He implied when he left that there was still a problem - so maybe it is flushing the system. I didn't really understand what he said the problem was (his English wasn't good). Something about pressure building up in the system somewhere???

So now I'm not sure what to do.

 

[swidders]

Well, the plumber came out and changed the ball valve in the CH header tank. It was working when he left, but of course, this evening now that he's gone, the water started dripping again.

He implied when he left that there was still a problem - so maybe it is flushing the system. I didn't really understand what he said the problem was (his English wasn't good). Something about pressure building up in the system somewhere???

So now I'm not sure what to do.

So, you paid him not to fix the problem?
Try draining the system down while tying the (new, unecessary) ball valve up. Clean out the small header tank. Pour sludge remover in, and refill the system. Let it run for a week or two and again drain down, allowing the small tank's valve to remain open and permit water to flow through until water flows through clear. Fill up, see how it goes, and if there's still a problem, get back on this forum.

 

[Bahco]

What is the water level in the tank when heating is off. Needs to be no more than 4 inches.

 

[calandra]

I just turned the CH off and left it off for a while. I checked the water in the attic tank and it was approx 4-5 inches - in any case, below the overflow pipe level. So the CH is on now and not dripping.

So was it possible that he left the tank full and now its back to normal so that it won't drip again - ok - I know it's wishful thinking.

Or will it just fill up again overnight and drip again tomorrow morning?

 

[swidders]

It may settle down - try adjusting the ball valve to a lower level, it may then drip for a day or so until it finds its level. If not, the flush as I have indicated and see what happens.

 

[calandra]

The heating is on now, and there is about 6-7 inches of water in the tank (again, just below the overflow pipe). No dripping.

But if I were to drain the small tank - how do I do it? It's stuck up in the rafters and I just used a cup to bail out a little water, but won't be able to drain it like that.

Also, the water in the tank is cold - is this how it is supposed to be?