Dripping Overflow Pipe...

JazzieJamJay · 2 Jun 2016

Hi to anyone reading this...

So, I'm going to put this into real Laymans terms because I don't want to confuse the matter. I am at work at the moment so can get more specific details/pictures later. I just want to get the ball rolling.

There is a small pipe on the front of my property that is constantly dipping water, about 2 drops per second. This is happening constantly. When I leave for work it is dripping, when I get home from work it is dripping and it is dripping when I go to bed. I have never seen it pour, only drip.

I have been in the loft and there is a small black box, it has what looks like a bin liner wrapped around it. I am lead to believe this black box feeds water into a large container (big foamy looking guy) that is almost directly below it in the wardrobe of my main bedroom.

Now...Having googled possible issues, I have ruled out a leaking Ballcock. I have emptied (almost completely) this black box off all water. When I do this, water is flowing into the box, filling it up until the floating ball reaches a certain height and it stops completely. I have held my hand and pieces of paper around the end where the water is pumped into the box to see if it was possible spraying in and I couldn't see it, but no leaks were noticed.

There is also a pipe separate from the box that aims into it. I believe this is a hot water vent. I don't understand exactly what its function is but I have a feeling it is the culprit.

BUT, I had a plumber in to see if he could sort the issue. He replaced a thermostat on the big foamy guy. There are two on the big foamy guy, a 'Boost' and I guess the other is just a 'Normal' one?

The plumber seemed to think that the thermostat was not switching off, heating and expanding the water up the pipe into the box and out the overflow. It seemed to work but only for a few days.

Anyway, the pipe drips onto my porch roof and I'm worried it will damage the structure.

I hope you have read this far and the information I have provided makes some sense at least! Please help and tell me its an easy and inexpensive fix.

Thanks

James

Hugh Jaleak · 2 Jun 2016

Right, a few basics. The 'black box' is a cistern, and the 'foamy guy' is a hot water cylinder. Cistern feeds cold water into the cylinder, where it is heated and then goes off to the hot taps. By sound of the matter you have 'Economy 7' or similar heating, whereby the cylinder is heated overnight using cheap rate electricity. Bottom immersion is the E7 heater and heats the whole tank, top immersions heats top section of tank for when you run out of hot water and you need to heat some more, but as it's using full price electricity, it only heats some of the tank to save money.

What we need to know is, when the overflow is dripping, has the water level in the cistern in the loft, risen to the overflow level? It is possible the thermostat has failed on one of the immersions, but if one has already been replaced, it is unlikely to have failed again. Is the top immersion on or off? Bottom should only be working overnight, so if it is faulty, by the time evening has come I would have expected the cylinder to have cooled sufficiently to stop overflowing.

Lastly, do you have any other type of boiler in the property, and have you checked the toilet cisterns to make sure they are not the cause?

JazzieJamJay · 2 Jun 2016

Hi Hugh,

Thanks for the quick reply, much appreciated.

Hugh Jaleak said:
has the water level in the cistern in the loft, risen to the overflow level?

Yes

Hugh Jaleak said:
Is the top immersion on or off?

Is this the thermostat? If so, its on.

Hugh Jaleak said:
do you have any other type of boiler in the property

No

Hugh Jaleak said:
have you checked the toilet cisterns to make sure they are not the cause?

How would I determine if this was the fault?

Thanks again!

James

JohnD · 2 Jun 2016

If the immersion thermostat was sticking on, then (1) the hot water from the taps would be scaldingly hot, and (2) your electricity usage would be abnormally high. Is either the case?

Have you got a stop=cock or service valve to turn off the supply to the ball-cock in your cold water tank(s)?

I would expect to see two cold tanks in your loft, a big one and a little one.

Which one is full of water up to the overflow outlet? Can you see where the overflow pipe goes, and does it seem to be the one that is dripping?

To check the cisterns, take the lids off and look at the water level. Is it surprisingly high, and does it reach the overflow outlet? If you flush your WC and run outside, does the drip stop until the cistern has time to refill?

Photos inside your cisterns and water tanks, showing the levels and the valve, will help.

Also photos of your hot-water cylinder. What colour is it? Does it have a matching, smaller tank with a removable lid, on the top, with pipes running between the two? Like this one?

Or is it single-piece, like this one (no "waist")

Hugh Jaleak · 2 Jun 2016

Only have 2 cisterns John if there's a gravity CH system. Combi or sealed system doesn't need a F&E cistern.

James, switch top immersion off, if you don't need it, it should be for topping up, bottom heater should be heating the whole tank overnight on E7, see if this helps matters. Toilets, see if there's a plastic overflow pipe heading towards outside. If there is, left the lid off the cistern and see where the water level is at.

JazzieJamJay · 4 Jun 2016

Hugh Jaleak said:
Only have 2 cisterns John if there's a gravity CH system. Combi or sealed system doesn't need a F&E cistern.

James, switch top immersion off, if you don't need it, it should be for topping up, bottom heater should be heating the whole tank overnight on E7, see if this helps matters. Toilets, see if there's a plastic overflow pipe heading towards outside. If there is, left the lid off the cistern and see where the water level is at.

Hi Hugh,

I never seem to have much hot water, even in the morning. I still have to switch on the boost in the kitchen to get enough to do the dishes!

I can see the pipe lead from the cistern in the loft to the outside so I confident its not the toilet.

Would pictures of anything help? Should I still turn off the top thermostat/immersion?

James

Hugh Jaleak · 6 Jun 2016

Sounds like the bottom immersion isn't working, I would get it checked out, that it is ok, and that the E7 is switching in when it should overnight. When the overflow is dripping, can you go and have a look in the cistern in the loft, above the hot water tank and see where the level is at?

JazzieJamJay · 7 Jun 2016

Hugh Jaleak said:
Sounds like the bottom immersion isn't working, I would get it checked out, that it is ok, and that the E7 is switching in when it should overnight. When the overflow is dripping, can you go and have a look in the cistern in the loft, above the hot water tank and see where the level is at?

I'll have a look tonight and post a picture or two. Every time I have a look the level is just at the edge of the overflow pipe. So I think it is constantly filling up slowly, i.e there is no sudden fill up and spill over of water.

Hugh Jaleak · 7 Jun 2016

Ok, but bear in mind immersions fail at the extremes, they either don't work at all, or don't switch off, hence boiling the water. You'd know if it was boiling though, it would be making a hell of a racket, the loft would be full of steam and I would be switching it off bloody quick, as there have been fatalities where boiling water has poured through the ceiling.

I'd still suspect a faulty ballvalve in the cold water storage cistern, if this problem is continuous.

polesapart · 8 Jun 2016

JazzieJamJay said:
when I get home from work it is dripping

Locate and turn off your mains stopcock before going to work. Drip on return?

dilalio · 8 Jun 2016

Is water in the cistern warm?
If not then your ball valve must be letting by... It should not drip at all when shut off! You need to watch it for several minutes to ensure that no drip comes from it, into the cistern.