My brother has had a problem for a while with hot water occassionally going up from the hot tank into the cold tank, not by the overflow but by the pipe that feeds the hot tank. I've been in the loft when it happens and the water is hot and the plastic tank can get soft. Water goes out the overflow. He has had the valve that controls the water/heating/both checked and that is ok and he has had mixer taps replaced. Any ideas anyone please?
HOT WATER GOING INTO COLD TANK
- Thread starter remus
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My brother has had a problem for a while with hot water occassionally going up from the hot tank into the cold tank, not by the overflow but by the pipe that feeds the hot tank. I've been in the loft when it happens and the water is hot and the plastic tank can get soft. Water goes out the overflow. He has had the valve that controls the water/heating/both checked and that is ok and he has had mixer taps replaced. Any ideas anyone please?- Joined
- 22 May 2007
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The coil in the indirect hot water cylinder has a hole in it. 
- Joined
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If he has two tanks in loft and the water is rising up the cold feed of the lowest tank then that is the problem.....coil.
I don't think it does.bobthebender said:The coil in the indirect hot water cylinder has a hole in it.
But it isn't doing that - it's rising up the cold feed into the CSS.bobthebender said:
I really don't think he is, cm.corgiman said:
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Softus said:I don't think it does.bobthebender said:The coil in the indirect hot water cylinder has a hole in it.
But it isn't doing that - it's rising up the cold feed into the CSS.bobthebender said:
I really don't think he is, cm.corgiman said:
35 years as a lead basher,pipe bender and gas fitter tells me i probably am
It does not matter which tank it is rising into if that tank is lowest then that's where it will go.
You knew that though Softus
Well, you're all being very kind and patient with me, so I've been back over the topic to see if I've misread something.
Firstly, bobthebender, of course you're right that water will find the lowest point, and that a holed cylinder coil will fill whichever cistern is lower/lowest, and you're right that I knew that. I didn't mean to imply that anyone was wrong about that.
However, the OP is demonstrating a good understanding of the principles involved, and there's a consistent message from him/her that the water is flowing from the cylinder, back up its cold feed, into the CSS.
So, assuming that all of the obvious ball valve checking has been done, it all comes down to the relative heights of the cisterns; if the F&E (water level) is higher, then the cylinder coil is holed/split; if the CSS level is higher, then it can't be.
Given that we're waiting to hear which of these applies, and given that it's commonplace for both cisterns to sit on the same base, I was just playing my hunch card.
It's a risk that I'll be wrong, and you'll then all spank me with basin wrenches and spray my nads with expanding foam, but I was feeling mischievous so I'm taking that risk.
Firstly, bobthebender, of course you're right that water will find the lowest point, and that a holed cylinder coil will fill whichever cistern is lower/lowest, and you're right that I knew that. I didn't mean to imply that anyone was wrong about that.
However, the OP is demonstrating a good understanding of the principles involved, and there's a consistent message from him/her that the water is flowing from the cylinder, back up its cold feed, into the CSS.
So, assuming that all of the obvious ball valve checking has been done, it all comes down to the relative heights of the cisterns; if the F&E (water level) is higher, then the cylinder coil is holed/split; if the CSS level is higher, then it can't be.
Given that we're waiting to hear which of these applies, and given that it's commonplace for both cisterns to sit on the same base, I was just playing my hunch card.
It's a risk that I'll be wrong, and you'll then all spank me with basin wrenches and spray my nads with expanding foam, but I was feeling mischievous so I'm taking that risk.
remus said:
A failed immersion heater thermostat will do it too.thats exactly what happened to me
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