Thanks for the reply. Do you advise me to have to cut part of the coil and replace it or with just the welding I would have to stop the water leaking? I have never done it, but since it is my heater, nothing happens if I have lost it, hehehehe thanks.
If the filtration is due to wear, you must change the coil, because it will break elsewhere.
Being a union you can weld it.
The technique used in welding is of the utmost importance so that it is well repaired.