what would cause a copper hot water storage cylinder to collapse?

[Marty32]

Evening all

Just looking for some scenarios so I don't ending up making any mistakes out in the field?

Cheers

Mar

 

[mountainman]

Never seen it happen but I suppose if the cold feed and vent were frozen and you drew off water the negative pressure created could allow the cylinder to collapse.

 

[hammers4spanner]

Collapse ,
cant say ever heard of it happening to be honest , as mountain man says a possible scenario or another would be an fat plumber leaning on it!

 

[M.Joshi]

Wasn't there a thread discussing this not too long ago? Something related to draining a tank and changing the immersion heater.

 

[wheeto]

Never seen it happen but I suppose if the cold feed and vent were frozen and you drew off water the negative pressure created could allow the cylinder to collapse.

I'm not sure you'd get the required pressure from just drawing water off (though I'm not saying it can't happen). I think it's more likely to happen as the water in a bunged cylinder cools.

 

[mountainman]

Possibly, but it is atmospheric pressure that collapses the cylinder so it wouldn't take much of a differential pressure to do some damage to a copper cylinder.

 

[Destroyer2813]

U can blow the bow in the bottom out by leeting someone in to cap off the vent and replace it with a auto air vent

 

[scorps]

Never seen it happen but I suppose if the cold feed and vent were frozen and you drew off water the negative pressure created could allow the cylinder to collapse.

Saw this happen when i was an apprentice many moons ago,un-froze the expansion and re-filled,it opened up again but with a load of creases,it made everyone laugh in the brew cabin for many a year

 

[mountainman]

Cheers Scorps, you've validated that my one remaining brain cell is still working

 

[Mike Jackson]

I've seen one split where the open vent and feed had frozen and the boiler came on. Made a right mess. After fitting a new cylinder it took me hours to defrost the pipework in the loft to fill and test the new cylinder.

 

[AWheating]

what would make a cylinder collapse??? my fat backside as im trying to get the lagging off to get a few more quid down the scrap yard

 

[Mike Jackson]

Best way to get the lagging off is to cap the cold feed and stick a hoover on the top. The cylinder will collapse and the lagging fall off. Assuming you haven't had to smack a hole in it to syphon the water out where the drain off doesn't work. I just jump on them in this instance.

 

[Poxi]

Never seen it happen but I suppose if the cold feed and vent were frozen and you drew off water the negative pressure created could allow the cylinder to collapse.

Saw one that had imploded due to this exact fault back in the Eighties. ( God am i that old).

 

[mountainman]

Saw one that had imploded due to this exact fault back in the Eighties. ( God am i that old).

I'm that old too but i must have led a sheltered life.
My education is incomplete Master. sob!

 

[Resolute]

I guess if you had a blocked vent pipe and blocked feed then tried using a wet vac to suck the blockage through you could end up collapsing the cylinder?!

 

[mountainman]

That reminds me of a GF years ago who's party piece involved a golf ball and a length of garden hose.

 

[AWheating]

That reminds me of a GF years ago who's party piece involved a golf ball and a length of garden hose.

its easier to play golf with a golf club??

 

[tamz]

It can and does happen. I've seen it twice. the first was caused by frozen pipes the second i did when syphoning a cylinder (it was coming out)
Just needs the right circumstances, which with the grade of so called plumbers now doing this job who don't even know the absolute basics and fit vented cylinders with no expansions because they are thick as mince, it will.
Also saw one with the rse turned out due to frozen pipes too and the immersion being switched on.

Here is the one i collapsed when syphoning. The hose in the draw off was pretty tight fit but not airtight. Well i would put it up if the thing would let me!
I'll try it again later

 

[dave1]

I've seen one split where the vent was removed and an aav fitted.... Messy!

 

[mountainman]

its easier to play golf with a golf club??

Dunno if she played golf, pretty good cheerleader though.

 

[TBServices]

My mates cyl imploded on Xmas eve a couple of years ago. Can only imagine that the vent was blocked with ice, and when the pressure built it it blew the ice plug and caused a vacuum. Only time I've ever seen it.


Sent from my iPad using Tapatalk HD

 

[marvoni]

It's quite common where I am to have water cylinders collapse, especially the older copper type. There are usually two anti-vacuum valves fitted at the cylinder to prevent it but sometimes they stick closed with limescale or sometimes they're incorrectly installed or missing entirely. Here's a photo of my cylinder, you can see the two vacuum valves on stalks at the top of the pictures.

 

[M.Joshi]

I remember Tree of Knowledge! The heat from the tank can't be doing those CDs much good!

 

[marvoni]

Yep, the Tree Of Knowledge is a good set, unfortunately my kids aren't interested in any learning aid that's not electronic.

About 20 years ago the cylinder developed a leak on one of the swaged seams. When I dismantled it to weld it I upgraded the insulation to closed cell pellets and added an internal reflective blanket so the outer casing is stone cold.

 

[M.Joshi]

Yep, the Tree Of Knowledge is a good set, unfortunately my kids aren't interested in any learning aid that's not electronic.

It's a shame - these series and other Knowledge series were a good source of information back in the day! I think mine are confined to loft too!