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hi guys,
just got called out to a job this evening, 4 other plumbers have been prior to me...this has been going on for a year!
its a mains pressure h j cooper hot water cylinder that makes a banging noise randomly, its a very loud bang that you can hear all through the house,
i was sent by apex to replace the cold water expansion valve, I isolated the two ball valves either side of the cwe at the inlet to the cylinder, opened up the lever on the cwe to relieve the pressure and the bang went off like a shotgun, then the drain oin the cold water expansion felt hot.
is there anyway it could be a issue with the tempering valve non return? the take off line on the cwe does go up to the tempering valve,
from what the customers have told me ALL the valves (including the limiting valve in the garage ) have been repaced
the customers are starting to get frustrated.....
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hi guys, Roberto i have a 2006 300ltr `H J Cooper h/p cyl myself but dont have the problem you describe, have you contacted `RINNAI`as they took coopers over some time ago sounds like a strange problem that will/could result in a serious leak, needs sorting for sure, good luck and keep us posted, cheers
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I have had this issue before. It will be a faulty element ARCING under water.
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surely a arcing element would pop a circuit breaker or rcd !due to earth leakage
what model coopers is the cylinder? stainless steel coil wet back by any chance ?
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hi guys, yeah very strange, i suppose expansion and contraction could let a drop or two in then seal before arcing but i imagine that the element would slightly `faulty`from new, long shot but.... cheers
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Hi Robbo, not externally. Im talking about inside the tank and submerged under the water if the element has a crack it will arc under water and cause a banging noise. This is not uncommon when the element is on its way out or damaged for other reasons.
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How loud is that banging noise if the element has a crack? Is it unmistakable? I'm having a paranoia that I'm hearing something like that.
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It can get pretty loud