Leak from both heating elements in Pulsacoil BP

Hello

I've noticed that my 7yo Pulsacoil is leaking form both heating elements when the cylinder get cold. The leak is directly from the threads, and only occurs after using larger amount of hot water. In the morning, after the heating period, no leaking.
A plumber inspected the unit and noticed that the front wall of the cylinder cover is bulged, which may suggest that the cylinder has expanded above normal or even cracked. In that case the changing the heating elements is pointless


Did anyone had similar problem?

Yes it would appear to be terminal.

But to make sure. You could drain. Fit 2 immersion blanks.
Then refill. Unit will be cold. See if it leak.

But also check the heater gaskets.
If yours have the O rings then they do leak.
In that case you can fit 2 normal heater washers / gaskets.
But might consider 2 new heaters at the same time ( XB 482 complete with new stats)

Mike