Please help with hot water cylinder!

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neilyounguk

4 posts

Wannabe Geek

#220116 26-Jul-2017 19:17

Hi,

Somehow my hot water tank is leaking somewhere. The water seems to somehow be coming out of the drip tray and making my ceiling damp.

In picture 1 you will see the pipe that goes into the drip tray. When I leave it in the drip tray it leaks somewhere and my ceiling gets wet. When I take the pipe out and put in a bucket the ceiling doesn't get wet.

Picture 2 shows the other side of the tank and the outlet pipe that takes the water out the drip tray. I tested filling the drip tray with water and the outlet pipe seems to be doing its job and taking some of the water out without leaking.

My only conclusion would be that there is a hole in the drip tray somewhere. But I can't see any evidence of this and this issue has only presented itself recently so I don't know what would cause a hole.

Or could the water be coming out the pipe too fast and overflowing over the top of the tray? I don't think this is the case as there isn't that much water going into the bucket when I put the pipe in there.

Any suggestions appreciated!

Many thanks

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2487 posts

Uber Geek
Inactive user

#1831811 26-Jul-2017 19:27

The bricks have probably punctured the tray causing a slow leak.

frankv

5680 posts

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Lifetime subscriber

#1831832 26-Jul-2017 20:20

My question would be why is water coming out of that pipe? Better to fix that than the drip tray. But better to fix both.

I doubt that it's too fast for water to run out of the outlet pipe... that looks bigger than your leaking pipe. But there could be leaks in the try or outlet pipe.

It could also be that water is running down the pipe and dripping off before it gets to the drip tray.

Ceiling damp spots are notoriously difficult to diagnose; water can trickle down rafters and joists for some distance. I guess you're sure that the cylinder and/or pipe are the cause of the problem?

JayADee

2148 posts

Uber Geek

#1831854 26-Jul-2017 21:14

Are you sure the damp part of your ceiling is under the drip tray?

gzt

17127 posts

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Lifetime subscriber

#1831870 26-Jul-2017 21:19

How much water in the bucket after 24hr?

Bung

6484 posts

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Subscriber

#1831898 26-Jul-2017 22:45

frankv:
My question would be why is water coming out of that pipe? Better to fix that than the drip tray. But better to fix both.

I doubt that it's too fast for water to run out of the outlet pipe... that looks bigger than your leaking pipe. But there could be leaks in the try or outlet pipe.

It could also be that water is running down the pipe and dripping off before it gets to the drip tray.

Ceiling damp spots are notoriously difficult to diagnose; water can trickle down rafters and joists for some distance. I guess you're sure that the cylinder and/or pipe are the cause of the problem?

The same reason that open roof vents sometimes drip after you've used hot water. The cold water refilling the tank expands as it is heated. The pressure relief valve with the yellow tag is matched to the pressure reduction valve on the inlet.

What is the paper bulldog clipped to the rim of the catch tray for? That could be sucking water over the edge by capillary action.

elpenguino

3423 posts

Uber Geek

#1831899 26-Jul-2017 22:52

You could lay out news paper or similar underneath to get a handle on where the drips originate from.

Most of the posters in this thread are just like chimpanzees on MDMA, full of feelings of bonhomie, joy, and optimism. Fred99 8/4/21

Aredwood

3885 posts

Uber Geek

#1831906 26-Jul-2017 23:41

Do you have single lever mixer taps in the house? If so, turn them on 1 at a time, full bore with the handle in the centre. See if this causes water to flow out the pipe from the relief valve.

Also try turning the cylinder off for a day so it will cool down. Turn it back on again and look in the ceiling when it is reheating. The pipe from the relief valve should start dripping due to thermal expansion, See where the leak through the ceiling is coming from.

Note that that cylinder will be at least 30 years old. And it is low pressure. Consider getting it replaced with a mains pressure hot water system. It has probably been installed in the ceiling to increase the hot water pressure a little bit.

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Beny

22 posts

Geek

#1831907 26-Jul-2017 23:46

Aredwood:

Do you have single lever mixer taps in the house? If so, turn them on 1 at a time, full bore with the handle in the centre. See if this causes water to flow out the pipe from the relief valve.

Also try turning the cylinder off for a day so it will cool down. Turn it back on again and look in the ceiling when it is reheating. The pipe from the relief valve should start dripping due to thermal expansion, See where the leak through the ceiling is coming from.

Note that that cylinder will be at least 30 years old. And it is low pressure. Consider getting it replaced with a mains pressure hot water system. It has probably been installed in the ceiling to increase the hot water pressure a little bit.

Would you have to change all the taps if you were to change the cylinder to Mains pressure?

Aredwood

3885 posts

Uber Geek

#1831910 27-Jul-2017 00:08

Beny:

Would you have to change all the taps if you were to change the cylinder to Mains pressure?

Most of the time no. Sometimes you need to remove flow restrictors. Occasionally you need to replace the shower mixer, typically if it is something like an old Dorf or Markham ect.

I see lots of houses with cheap single lever tapware, that is often useless on low pressure. In these situations, normally mains pressure is the best long term solution. Sure, there are tricks to improve low pressure shower performance, But often the flow to the sink and basin is still terrible.

Often to get low pressure working properly, you need 1960s design tapware. Which no one wants in a new bathroom or kitchen.

MikeAqua

7782 posts

Uber Geek

#1832014 27-Jul-2017 08:55

The first photo shows an area near the seam at the base of the tank that has white corrosion on it.

We had exactly that sort of corrosion when our HWC was slowly leaking.

But .... +1 for replace the cylinder.

Mike

debo

307 posts

Ultimate Geek

#1832042 27-Jul-2017 09:37

I had a pin hole leak in my cylinder. Spent a fortune replacing it with mains pressure. By the time the new cylinder went in, the leak had clogged up and fixed itself.

Wheelbarrow01

1723 posts

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Trusted

Chorus

#1832081 27-Jul-2017 10:11

Aredwood:

Beny:

Would you have to change all the taps if you were to change the cylinder to Mains pressure?

Most of the time no. Sometimes you need to remove flow restrictors. Occasionally you need to replace the shower mixer, typically if it is something like an old Dorf or Markham ect.

I see lots of houses with cheap single lever tapware, that is often useless on low pressure. In these situations, normally mains pressure is the best long term solution. Sure, there are tricks to improve low pressure shower performance, But often the flow to the sink and basin is still terrible.

Often to get low pressure working properly, you need 1960s design tapware. Which no one wants in a new bathroom or kitchen.

Hmm I am having similar issues at the moment. I have renovated a rental property and installed a whole new bathroom suite including basin and shower mixers which were supplied by Millens and carry their name. The water pressure to the basin and shower are virtually non-existent now - they both just dribble at the moment. The old 1970's shower and separate taps were fine, and the old kitchen mixer which I have not replaced still has great hot water pressure.

There is clearly a huge difference between good quality tapware and the crap that I have bought. I now face having to rip the bathroom tap and shower mixer out and replace them, because the bathroom is completely unusable until I do.

Hammerer

2476 posts

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#1832099 27-Jul-2017 10:45

We moved our low-pressure hot water system from the low end to the high-end of low-pressure to resolve a similar issue when we added a second bathroom. We took out the tank in the ceiling cavity which used to gravity feed the hot-water cylinder and replaced it with a pressure-reducing valve. This worked very well particularly as one of our main concerns was to prevent the hot-water wastage that comes with mains-pressure showering.

neilyounguk

4 posts

Wannabe Geek

#1832217 27-Jul-2017 13:23

Hi all,

Thanks for the tips.

The wet patch on the ceiling is definitely from the drip tray, as when I put the pipe in the bucket the issue goes away. I would say in the space of a week about 5 litres of water goes into the bucket

The bulldog clip was put on as there was a slight split in the plastic at the top, so thought I would see if it was leaking there. But it wasn’t the place it was leaking

I think the best course of action would be to put a high pressure new cylinder in but I will probably sell the house in couple of years and won’t get the value from it.

My only conclusion is that there is a hole in the drip tray somewhere but I can’t find it!

Thanks

elpenguino

3423 posts

Uber Geek

#1832554 27-Jul-2017 21:49

Can you fit a drip tray under the drip tray?

Most of the posters in this thread are just like chimpanzees on MDMA, full of feelings of bonhomie, joy, and optimism. Fred99 8/4/21

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