Steam generator iron staining clothes?

[wigglybeezer]

Have been given MIL's 'spare" steam generator iron, great at getting creases out of stuff that's been in the ironing pile for yonks but...somehow water(I think condensation collecting under the ironing board cover somehow rather than dripping from the iron) has been bleaching DH's dark shirts in patches. The iron is working well but I don't have the instructions, we live in a soft water area so i don't usually bother using descaler etc.
any advice from more experienced ironers?

Even soft water areas need to use descalers! I would suggest you both descale it and clean the soleplate - often an accumulation of gunk leads to a build up on any iron and then it splurts out and causes staining. Lakeland do some very good tiny spiral brushes (like bottle brushes) that can get in the holes. Or you can use a pipe cleaner.