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Hi

I have a leak from one of the pipes, going into the hot water cylinder, in the airing cupboard. There are 2 pipes going into the cylinder on the left hand side, (I think it is called a vented cylinder - colder water tank in loft) and it is the top pipe which is leaking, (the one with yellow cloth and black tie wrapped around it in pic) I will attach 2 pictures I have taken. It leaks where the pipe goes into the cylinder. Is it called a flange? I saw a video on youtube showing a similar leak.

As you can see, I am soaking up the water with absorbent cloths/sponges at the moment. I first discovered the leak, as it had stained the kitchen ceiling and when I went to investigate to see if it was the hot water cylinder, the leak had soaked some of the floorboards in the cupboard. They have dried out, since I put the cloths/sponges there and keep wringing them out.

It seems to get worse, whenever I run a bath/draw hot water.

I know this needs an urgent fix from a tradesman but I have been shielding since the beginning of the pandemic and still don't want anyone coming in the house yet.

Is there a product I could buy to try and temporarily fix the leak? I am not a diy-er and have no knowledge of plumbing etc. I also find things difficult because of my illness but hopefully, could manage to apply a product if there was a suitable one. The other difficulty is there is so little space to work in, as the wall and cylinder are so close together, so it's really difficult to actually look at the leak itself. I managed to take the pic where the pipe goes into the cylinder, by aiming the camera towards the hole and hoping for the best.

Another question: Because it seems to leak more when/after drawing hot water for bath etc, I am trying to avoid doing this. Is it unsafe for the same hot water to be heated over and over again in the cylinder, (have an ancient gravity fed system from the 1970's but cylinder has been replaced before, when the old one leaked) Could it cause Legionnaires Disease, or could it overheat if all the water evaporated over time? I have been running a bath every few days, to make the cylinder fill with fresh water then but it is so inconvenient, as I have to wring out the cloths much more often afterwards and worry overnight when sleeping.

Thanks very much in advance for any advice you can give me. Cylinder leak IMG_1852[9279].jpgCylinder leak IMG_1858[9281].jpg
 
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Hi

I have a leak from one of the pipes, going into the hot water cylinder, in the airing cupboard. There are 2 pipes going into the cylinder on the left hand side, (I think it is called a vented cylinder - colder water tank in loft) and it is the top pipe which is leaking, (the one with yellow cloth and black tie wrapped around it in pic) I will attach 2 pictures I have taken. It leaks where the pipe goes into the cylinder. Is it called a flange? I saw a video on youtube showing a similar leak.

As you can see, I am soaking up the water with absorbent cloths/sponges at the moment. I first discovered the leak, as it had stained the kitchen ceiling and when I went to investigate to see if it was the hot water cylinder, the leak had soaked some of the floorboards in the cupboard. They have dried out, since I put the cloths/sponges there and keep wringing them out.

It seems to get worse, whenever I run a bath/draw hot water.

I know this needs an urgent fix from a tradesman but I have been shielding since the beginning of the pandemic and still don't want anyone coming in the house yet.

Is there a product I could buy to try and temporarily fix the leak? I am not a diy-er and have no knowledge of plumbing etc. I also find things difficult because of my illness but hopefully, could manage to apply a product if there was a suitable one. The other difficulty is there is so little space to work in, as the wall and cylinder are so close together, so it's really difficult to actually look at the leak itself. I managed to take the pic where the pipe goes into the cylinder, by aiming the camera towards the hole and hoping for the best.

Another question: Because it seems to leak more when/after drawing hot water for bath etc, I am trying to avoid doing this. Is it unsafe for the same hot water to be heated over and over again in the cylinder, (have an ancient gravity fed system from the 1970's but cylinder has been replaced before, when the old one leaked) Could it cause Legionnaires Disease, or could it overheat if all the water evaporated over time? I have been running a bath every few days, to make the cylinder fill with fresh water then but it is so inconvenient, as I have to wring out the cloths much more often afterwards and worry overnight when sleeping.

Thanks very much in advance for any advice you can give me.View attachment 47673View attachment 47674
Hav3 you tried just nipping it up abit? See if you can tighten it a little more ( but don’t go mad)
 
Hav3 you tried just nipping it up abit? See if you can tighten it a little more ( but don’t go mad)
Out of an abundance of caution, I wouldn't try that in the OP's circumstances because there's a risk that taking a spanner to it it'll make matters worse. Obviously a plumber could handle any problems but the OP isn't a plumber...

I would suggest that the OP contact a reputable local firm and explain the circumstances. They should be able to do the work needed in a way that is safe, while the OP stays in another room and communicates with them by phone if necessary. Leave a window a jar while the work is in progress and give the area they've been in a chance to 'blow through' once they've left.

I don't normally suggest big firms like British Gas for small plumbing jobs because they are expensive, but they may be worth considering as they should have the resources (PPE, training, etc,) needed to work in buildings occupied by shielding persons.
 
Out of an abundance of caution, I wouldn't try that in the OP's circumstances because there's a risk that taking a spanner to it it'll make matters worse. Obviously a plumber could handle any problems but the OP isn't a plumber...

I would suggest that the OP contact a reputable local firm and explain the circumstances. They should be able to do the work needed in a way that is safe, while the OP stays in another room and communicates with them by phone if necessary. Leave a window a jar while the work is in progress and give the area they've been in a chance to 'blow through' once they've left.

I don't normally suggest big firms like British Gas for small plumbing jobs because they are expensive, but they may be worth considering as they should have the resources (PPE, training, etc,) needed to work in buildings occupied by shielding persons.
Are you suggesting that British Gas (who will charge three figures minimum for that) have all the resources but any other tradesmen don’t?
I have been working through the whole pandemic and I’ve entered many homes/ businesses without any issues.
If the op isn’t up to it I would suggest contacting a reputable plumber as appose to British Gas.
Any decent tradesman take the relevant precautions.
Im sorry but as a plumber of 30 years plus I completely disagree with your advice you have given the op.
 
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Thank you both for your replies. I would be too scared to try and tighten it, just in case it did make matters worse. Very tempting to try but I hope I can resist!

I am also too scared to have a tradesman in. I know they might say it can be done in a safe way (PPE, open window, me in another room etc) but I still don't want to risk it. I have heard of quite a few shielders who just took one little risk (such as this) and were unlucky enough to go down with the virus.

Is there no product at all, which would seal it up for now? Would be difficult for me to apply without me being able to actually see the leak (not enough room to get my head in position needed). I have seen sprays and putty etc. Any ideas? Or any better way than cloths and towels to catch the water from the leak?

Also, could someone answer my question about same water in cylinder being heated up over and over again, if I don't draw any hot water, until problem fixed? Worried about Legionnaires and/or cylinder burning out in the end.

Thanks again.
 
Also worried about the water in tank in loft not being drawn for ages and what problems that could cause? I think the cold water taps upstairs are being fed from the mains. So, I am worried about the water in the cylinder and in the tank not being refreshed.
 
So long as your cylinder is heated to 60°C, that will be enough to kill legionella. (Technically 55°C is sufficient, but it takes an hour to do so). It is when water is stored for long periods at a medium temperature, say 40°C, that the bacteria is most likely to breed.

Even if you were to drink water with high levels of legionella bacteria (which you are not), that would not necessarily be a problem. You'd have to choke to inhale the water. Legionella in the digestive tract have no effect - it is when they get into the lungs that the problems can start. The greatest risk, therefore, is if you are using a shower that runs from a tepid cylinder.

The cylinder absolutely will not dry out or burn up. The cistern in the loft will naturally keep the cylinder full and replace any leaked water.

If your loft cistern ('tank') only fills the hot cylinder, then, while bacteria may breed in it (though less likely in cold weather than in the summer), these bacteria would be killed off once they get into the cylinder and are heated to 60°. You could always run a hot tap for 20 minutes (open the window and leave the room and shut the door while it runs) after you eventually have the leak repaired. This will flush the old water out of the system. Then let the cylinder heat through and leave it an hour before starting to use the hot water again, letting each hot tap run for 2 minutes once everything is heated through (again ventilating the rooms when you do so).

In terms of products, you can get a type of thick silicone sealant that is called "Fernox" LSX. It is suited for use with drinking water so you could give that a try. But only if you can locate the leak!

Have you not considered a shallow bowl, sardine tin, or similar to catch the drips? May be better than cloths and, if the source of the leak is warm and the area is open to airflow, some evaporation may take place at source (in a hard-water area you may even find the limescale where the water evaporates blocks the leak eventually... if you're really lucky).
 
Thank you so much for your very informative reply and advice Ric.

The cylinder is being heated to 60 degrees C. I hope so anyway. I have the boiler thermostat set to 150 degrees F. It is an ancient Vulcan boiler, so still in Fahrenheit! There is no thermostat on the cylinder itself that I can set.

Everything needs updating in the house and more and more jobs are piling up since the pandemic. This is the second plumbing problem that has arisen. The dishwasher hose is leaking under the sink as well, which is a real blow to me, with my illness. I can't do a temporary fix to that either, as again, I can't see exactly where the leak is coming from in the hose, before it leaks into cupboard.

With the cylinder leak and your suggested product to give a try, do you think I would be able to apply it just by feeling with fingers? Have you any idea from the first pic, which part is probably leaking, to give me an idea where I should apply the product? Probably difficult for you to answer that.

I do put a shallow plastic dish underneath the leak for extra security but it wouldn't be enough on its' own, as with the limited space between the pipes to place it, some of the leak still hits the floorboards around the dish.

Thanks so much again for your help with this. I really appreciate it!
 
I do put a shallow plastic dish underneath the leak for extra security but it wouldn't be enough on its' own, as with the limited space between the pipes to place it, some of the leak still hits the floorboards around the dish.
Another trick to try is to tie a piece of string around the pipe that is the source of the drip and arrange it so that capillary action causes the water to run down the string into a container. This gives you a bit more leeway when it comes to positioning the container.
 
PS We are in a very hard water area (Herts), so it would be fantastic if the limescale did eventually block the leak! I would be over the moon if that happened! 🤞
 
No BG Bashing
I would suggest that the OP contact a reputable local firm and explain the circumstances. They should be able to do the work needed in a way that is safe, while the OP stays in another room and communicates with them by phone if necessary. Leave a window a jar while the work is in progress and give the area they've been in a chance to 'blow through' once they've left.
Yes, spot on!👍
 
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I have been trying to investigate some more, to find exactly where the water is leaking out. I have been feeling inside the circular recess and I can't feel any water on the actual pipe/joins. The water is pooling at the bottom of the circular recess, (the cut out circle on left hand side where pipe goes into cylinder) then dripping down the cylinder to the floor. It feels like it might be coming from cracks in whatever is sealing that recess. I think I could feel cracks in the material (is it concrete or something?) with my fingernail. Again, I am not sure but I think I might have made it worse with my fingernail, as it is dripping faster now! Before, it was dripping about every 12 seconds and now it is dripping about every 6 seconds! Would "Fernox" LSX still be the right material to try and do a temporary fix please?
 
It may be hard to plug a leak with LSX if it dripping that fast, but since it's low pressure, may be worth a try. There shouldn't normally be sealing compound used in the manufacture of the cylinder. Is it limescale?
 
Hard to say if it is limescale, because of not being able to actually look at it.

In the first picture in my original post, you can see the blue colour of the cylinder and then what looks like a grey smooth compound inside the cut out circle. From feeling with my fingers, the water is coming from the bottom of that smooth grey compound, (though didn't feel smooth with my fingers), where it joins the bottom of the circular recess. Isn't that some kind of sealant?

I did wonder how the LSX would adhere, when the water is dripping so fast. Some products I have seen say adhere underwater but that sounds too good to be true.

During my investigations, I was able to get right down on the floor and see where the drips (3 of them now - one fast drip, two slow) were hitting the floor underneath the cylinder and I found a plastic box which was small enough to fit there and catch the drips. It fills up too quickly to last overnight though, so I have ordered a bar drip tray (narrow but long, so will fit), which, hopefully, should take longer to fill up. Best method so far, until the tray arrives, is 2 cloths pushed inside the recess, then a bath towel wrapped around the pipe.

Why does it get better when the water is being heated or the central heating is on? Is it to do with expansion that I have read about and why does it get worse if I run a bath? Is that pipe sending hot water from the boiler into the cylinder? As the weather has warmed up, I have had the heating on less, so maybe that's why it has been dripping faster. I'd like to understand the mechanics though.

Out of interest, what would happen if I attempted to turn off the cold water feed to the cylinder? I have seen the red wheel valve higher up but I am scared to try it. I wouldn't be able to drain the cylinder though.

Thanks very much for all your help Ric.
 
I't is possible the pipes flex and have strained the connexion to the cylinder. As you have noted, the pipes expand and contract very slightly with temperature, and, if on a long run...

I'm not sure what running a bath would change. Though the cylinder itself would get cold, the pipes should remain hot if the boiler is firing.

If you turned off the cold feed to the cylinder, the pressure in the cylinder would remain as the vent pipe would be full of water, though if the leak is that bad, the pressure should then fall to some degree once the vent from the cylinder empties (open a hot tap to empty the vent). Assuming you have a good quality gate valve that seals perfectly (they don't always), that is. If you want to try, MAKE SURE THE IMMERSION HEATER CANNOT SWITCH ON - otherwise someone will switch it on and the element will fail (if the water level drops). Sod's law. Risk is that this will airlock the hot pipes afterwards, but if you aren't using hot water for now, that isn't a big problem.
 
Thanks Ric.

What did you mean when you said, "and, if on a long run..."

Hoping I am wrong about the bath then, as that would mean I could go back to having baths again. That is, if I don't try turning off the gate valve. I don't know what you mean about the immersion heater, as there isn't one. Just the cylinder, which the boiler heats the water for. Do you mean the switch which is in the airing cupboard? Should that be switched off if I did decide to attempt to turn off the gate valve? Not sure I want to risk another problem with airlock. Not that I know what happens with an airlock.
 
PS What you said about the boiler firing when running bath. It wouldn't be firing if I am having a bath when boiler is off. Maybe the solution for that problem is to make sure I heat the water via the boiler when running the bath?
 
What did you mean when you said, "and, if on a long run..."
Sorry! 'On a long pipe run'. I.e. the longer the length (the straight run) of pipe, the more significant the expansion.

1613507860007.png

Isn't that an immersion heater? Does it have a wire connected to it? And are you sure it isn't leaking from there and running down? Unlikely but worth a quick look.

You stated, "Maybe the solution for that problem is to make sure I heat the water via the boiler when running the bath?". I can't see what harm it would do to try.

Basically an airlock can result if the pipework is not well designed. Once the pipe is empty, it fills with air and the water pressure is insufficient to clear the air. It shouldn't happen at all, but plumbing mistakes are often found and plumbers are used to the tricks required to get things flowing again. The risk is no hot water when you re-open the red valve due to air blocking the pipework. Not damaging or dangerous, but annoying.

It is also possible that the valve may not reopen when you want it to, especially if you turn it off too hard. Often the valves used for this sort of application are gate valves. Good gate valves work well, but many are built to a low price and the quality suffers a lot (send us a photo?) You may be fine, but it's only fair to warn you.
 
Well, here I am, back again after 6 months. I am still in the same situation, (as in, I am still shielding, due to not being vaccinated and still have the leak in the cylinder). I got used to checking the drip tray I bought and emptying it regularly over the winter.

Over the summer and the warmer weather, I noticed the leak would slow right down when the boiler wasn't being used for long periods. So, I stopped using the boiler and just heated the water once a week, to keep the boiler in working order. I then started leaving it off for longer and running it once every 2 or 3 weeks.

Then one day, I noticed the pilot light had gone out, (it is a very old Vulcan Continental boiler from the 1970's). I looked up the instructions how to light it manually and was able to light it but it wouldn't stay lit. Every time I let go of the valve, the pilot light went out again.

I read the most common problem is a faulty thermocouple.

I have been in touch with a gas registered plumber and he could come and have a look for me (at both the boiler and the hot water cylinder) but I am still so nervous of catching the virus, especially, now we have the more contagious Delta variant.

Today, I tried to light it again and checked whether the flame was properly pointing towards the thermocouple metal end, as I had seen in videos online. I noticed the flame doesn't surround the thermocouple. The flame bends towards it at the bottom of the flame but the rest of the flame points upwards (ie vertically). It is very close to the thermocouple but more beside it, rather than surrounding it.

After the pilot light had gone out again, I touched the thermocouple end to see if it felt very hot and it did, so it is heating up but do you think it is heating up enough?

I don't see why the angle of the flame would have changed, as the boiler hasn't been touched inside for ages and the pilot light always stayed on before, so I don't see why it would suddenly be a problem.

When I have watched videos of lighting pilot lights, it looks like there is more than one flame? When I light it, there is just one flame. As I said, it bends a little at the bottom towards the thermocouple and the rest of the flame is vertical and is beside the thermocouple. The pilot light tube is angled towards the thermocouple but the flame doesn't engulf/surround the thermocouple metal tip bit.

Any ideas? I have seen the other possible problems in the videos but I don't want to touch anything else myself (eg cleaning the thermocouple tip, or the pilot light tube, or replacing the thermocouple with a new one).

Why would the pilot light suddenly go out when I stopped using the boiler for 2 or 3 weeks? It never usually goes out.

I have some pictures of the boiler I took a while ago but didn't take any of the pilot light chamber. I can try and do that another day if you need to see. Might be difficult to get a good photo of it, as it is right at the bottom, near the floor. I will attach the pictures I do have but I don't expect them to be of much use. You might enjoy seeing an 'antique' boiler though!

Thanks guys.

PS Sorry I didn't reply to your question back in February about the immersion heater you pointed out in the picture of the hot water cylinder Ric2013. There is no wire connected to it. I didn't even know it was an immersion heater, until you pointed it out. It has never been connected as far as I know.
 

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Sorry to say the virus is going to be around forever so we all just have to get back to normal safely

I would book him in and just be mindful of keeping 2m and wiping down after etc
 
Sorry to say the virus is going to be around forever so we all just have to get back to normal safely

I would book him in and just be mindful of keeping 2m and wiping down after etc
I know but as I said, I am not vaccinated, due to my illness, so I am vulnerable. I am hoping there might be a different type of vaccination or treatment in the future.
 
I understand your predicament but I can’t see anything short term eg 1-2 years 5-10 maybe
 
I'm old enough to know that's not a vulcan continental! Even older either a viceroy or a autostat first gas boiler I ever fitted as an apprentice.
 
I'm old enough to know that's not a vulcan continental! Even older either a viceroy or a autostat first gas boiler I ever fitted as an apprentice.
That's interesting. Thanks! Don't know how I thought I knew it was a Vulcan Continental. Unless I have seen it somewhere on the boiler. Were the 2 you mention Vulcan's, as it's definitely a Vulcan. It's on the door of the boiler and the label inside (which you can see in the last pic I posted).
 
Definitely a vulcan (factory still there stelrad rads made there now) the continental was physical smaller with a different control panel thermostat knob set in a panel at 45 degrees
 
Definitely a vulcan (factory still there stelrad rads made there now) the continental was physical smaller with a different control panel thermostat knob set in a panel at 45 degrees
I'd love to know exactly which model it is. Have just seen this advert, so looks like it isn't the Autostat model, as that one has controls on the outside. Ours doesn't have any controls at all on the outside.
 

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Ideal after they bought out Hattersley's re used the viceroy name on a range of commercial boilers (just to confuse matters)
 
Well, here I am, back again after 6 months. I am still in the same situation, (as in, I am still shielding, due to not being vaccinated and still have the leak in the cylinder). I got used to checking the drip tray I bought and emptying it regularly over the winter.

Over the summer and the warmer weather, I noticed the leak would slow right down when the boiler wasn't being used for long periods. So, I stopped using the boiler and just heated the water once a week, to keep the boiler in working order. I then started leaving it off for longer and running it once every 2 or 3 weeks.

Then one day, I noticed the pilot light had gone out, (it is a very old Vulcan Continental boiler from the 1970's). I looked up the instructions how to light it manually and was able to light it but it wouldn't stay lit. Every time I let go of the valve, the pilot light went out again.

I read the most common problem is a faulty thermocouple.

I have been in touch with a gas registered plumber and he could come and have a look for me (at both the boiler and the hot water cylinder) but I am still so nervous of catching the virus, especially, now we have the more contagious Delta variant.

Today, I tried to light it again and checked whether the flame was properly pointing towards the thermocouple metal end, as I had seen in videos online. I noticed the flame doesn't surround the thermocouple. The flame bends towards it at the bottom of the flame but the rest of the flame points upwards (ie vertically). It is very close to the thermocouple but more beside it, rather than surrounding it.

After the pilot light had gone out again, I touched the thermocouple end to see if it felt very hot and it did, so it is heating up but do you think it is heating up enough?

I don't see why the angle of the flame would have changed, as the boiler hasn't been touched inside for ages and the pilot light always stayed on before, so I don't see why it would suddenly be a problem.

When I have watched videos of lighting pilot lights, it looks like there is more than one flame? When I light it, there is just one flame. As I said, it bends a little at the bottom towards the thermocouple and the rest of the flame is vertical and is beside the thermocouple. The pilot light tube is angled towards the thermocouple but the flame doesn't engulf/surround the thermocouple metal tip bit.

Any ideas? I have seen the other possible problems in the videos but I don't want to touch anything else myself (eg cleaning the thermocouple tip, or the pilot light tube, or replacing the thermocouple with a new one).

Why would the pilot light suddenly go out when I stopped using the boiler for 2 or 3 weeks? It never usually goes out.

I have some pictures of the boiler I took a while ago but didn't take any of the pilot light chamber. I can try and do that another day if you need to see. Might be difficult to get a good photo of it, as it is right at the bottom, near the floor. I will attach the pictures I do have but I don't expect them to be of much use. You might enjoy seeing an 'antique' boiler though!

Thanks guys.

PS Sorry I didn't reply to your question back in February about the immersion heater you pointed out in the picture of the hot water cylinder Ric2013. There is no wire connected to it. I didn't even know it was an immersion heater, until you pointed it out. It has never been connected as far as I know.
The pilot light flame definitely doesn't hit the thermocouple tip like in this diagram. I wonder if it ever did though, as it hasn't been adjusted and no problems before now.
 

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