Ok I have open the boiler!I have notice that the leack is coming from the packing that is between each section? How can fix it?
If you really need to get some more time out of the boiler, inject liquid boiler seal. Follow the directions on the bottle.The stuff works but remember it is only a Band-Aid and could start leaking again ( usually at the most inopportune time !). Boilers last more than 5-7 years unless it has a defect in the casting or assembly.
Get a new one- check the warranty - it may still cover it. Protect the area w/ towels for the inevitable flood! Hurry! You were saved this time... They only last 5-7 years ...