CW tank overflowing randomly for approx 20 mins daily.
- Thread starter Bennychad
- Start date
Defo no immersion mate
There's a air bubble probably trapped in the top of the cylinder which is exerting pressure when heated and pushing the water back up the cold inlet, the vent should be straight off the cylinder top. In effect, a unvented cylinder.
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Hi John, would that cause the banging on the pipes?
When the cylinder is filled with water then the level will only be a few ins above the hot water take off due to the air above it being compressed by the ~ 2.5M head, it will then rise another few ins due to the expansion when the water is heated so there is bound to be some air entrained in the HW takeoff which will lead to banging in the pipes or something like that, normally in a vented system the water level is 2.5 to 3M above the HW take off so no air problems.
At the very least the HW take off should be relocated to the cylinder top.
At the very least the HW take off should be relocated to the cylinder top.
Thanks for that.
Would this only be when the boiler on?
As the banging happens in the night when it’s off.
My tenant say the boiler has been off since yesterday yet the banging happened this morning followed by the cwst expelling water like this.
Would this only be when the boiler on?
As the banging happens in the night when it’s off.
My tenant say the boiler has been off since yesterday yet the banging happened this morning followed by the cwst expelling water like this.
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Afraid I can't give a definitive answer to that, all I can say is that a mixture of air and water is not desirible in any pipework but might be unconnected with this nightly banging. You should try and sort out the HW cylinder problems first, you are certain that there are two vents, one goes up and over the F&E tank, the other, (where the water comes out) is over the CWST. Can you see how far this vent is from the HW cylinder, also cylinder details from the label, also the vertical distance from the HW take off to the cylinder top, might be barking up the wrong tree if this is taken off the top of the cylinder even though it doesnt look that way.
Have you tried tying up the ball valves yet?
When a filling valve is letting by, the overflow usually happens at night or early morning.
During the day, users running taps and flushing WCs use up the excess water before it tops the overflow. Pipes with a dip will syphon out water below the overflow once they start running.
When a filling valve is letting by, the overflow usually happens at night or early morning.
During the day, users running taps and flushing WCs use up the excess water before it tops the overflow. Pipes with a dip will syphon out water below the overflow once they start running.
If the di[p tube is only say 25MM below the o/flow level then it is hardly going to syphon water for 20 minues once the bottom of the dip tube is exposed, if in fact it is overflowing for those 20 minutes.
I see it dips below the normal level?, so what stops it syphoning continuously if the level reaches the top of the elbow?.
I see it dips below the normal level?, so what stops it syphoning continuously if the level reaches the top of the elbow?.
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Is the property a top floor flat ?
How long have you owned the property ,and when did your problem start ?
How long have you owned the property ,and when did your problem start ?
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