Overflow pipe leaking from megaflow

Soldato
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Hi just noticed when my boiler runs it appears that There is an overflow pipe that leaks outside on to the ground.

What could be the potential fix here?
 
Soldato
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I have not done that for a while

i will give that a go thanks

how often does it need to be done?
 
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I'd guess ours needs doing every 3 months or so. The first sign that it needs doing is that after the boiler has been heating the water, the hot water pressure is a bit higher than normal when turning on a hot tap - as soon as the tap has been opened the pressure is back to normal again.
 
Soldato
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Yes so assuming that method does not fix it
What are the other potential fixes or problems
Here!

more context
To follow tomorrow.....
 
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Hmm, if a pressure relief valve is either leaking or operating then I'd get someone qualified in to check it over. Those valves are there for safety reasons and not to be ignored...
Edit: I'd assumed you had tried regenerating the bubble without any success, if not then give that a go before calling anyone in!
 
Soldato
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so I replaced a tap recently (another thread), and the tap makes an annoying whistling sound so I closed the iso valves on hot and cold down a bit to reduce the noise.

I think this resulted in water going back out of the pipe to outside from the megaflow as I increased the valves to the tap and the problem seems to have stopped.

why would it leak like this when the tap's iso valves are reduced?
 
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I can't see how adjusting the tap isolation valves should affect the pressure in the cylinder. The only scenario I can think of is if your cold water pressure is higher than hot, and the your tap is somehow allowing the cold feed to pressurise the hot above the point where the pressure relief valve operates. (But a main point of a megaflow is to normally to have your hot water at the same pressure as the cold, so unless it's not installed correctly or you've got really high cold water pressure and there's a pressure reducing valve in play...)

Are you absolutely sure that the leaking overflow is from the megaflow? The pipe from the temperature & pressure relief valve (the one you turn to let air into the cylinder while regenerating the bubble) should go via a tundish before the overflow pipe to outside. Can you check that this is where the water is coming from? There is a second pressure relief valve in the cold feed valve which should have a separate overflow.

If you've regenerated the air bubble and the overflow is definitely from the megaflow, then there are two possibilities - either a pressure relief valve is faulty and leaking, or there is a genuine overpressure. Either way, I'd get an authorised company to come and check it over asap.

Good luck with it!
 
Soldato
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hey so the actual tundish did not feel very wet that's what I could not workout.

but there was definitely water spilling in the pipe that goes out into the wall. I could hear a little drip when the boiler was running, it sounded like the water was dripping to outside.

Looks better today there is no puddle. but what do u think it could have been?
 
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