Cylinder failure to ponder

[david3456]

I was starting a project to add another radiator so had drained the system down. Except water was still coming through. Isolate the cylinder and sure enough the water was coming out of the heating coil. More than 5 litres/hour.

The water level in the CH header tank is nominally about a foot below the level in the main tank. So the mystery is that if the circuits had become connected why had the CH header level not risen?

I can't imagine there was a fragility that finally failed when I introduced an 8 foot difference by draining that had survived thermal cycling.

Any thoughts? Or just weird?

 

[45yearsagasman]

I can't imagine there was a fragility that finally failed when I introduced an 8 foot difference by draining that had survived thermal cycling.

You are quite correct in assuming the header tank level would have risen to the main tank level, although it would have gone out the header tank overflow. Stranger things have happened to older indirect cylinders when drained. I think you have just been unlucky. It's time for a new cylinder. Consider stainless steel as an option. If you have an immersion fitted then that would have to be one suitable for S/steel.

 

[Agile]

And if stainless steel then not just the element but the thermostat pocket!

Both Screwfix and Toolstation were selling incoloy elements with COPPER pockets! Not likely to last long in a stainless cylinder!

Tony

 

[david3456]

It's time for a new cylinder. Consider stainless steel as an option. If you have an immersion fitted then that would have to be one suitable for S/steel.

Yes, the cylinder is probably 40 years old. Adaptors and dimensions have changed in that time but least there was enough give to line up the 28mm entry pipe.

I thought S/S looked attractive. Except the RM one I found didn't seem to have have an aperture for an immersion heater.

 

[45yearsagasman]

http://www.gledhill.net/

David.Try these people. Find a local supplier and they will also be able to supply a suitable immersion.
Notice the lack of exclamation marks in my text?