Dear TRNSYS users, thanks for your immediate answers. I know which was the problem now. I'll contact my distributor as soon as possible. Regards Luca Greco Luca Greco Mechanical Engineer Università della Calabria, 87036 Arcavacata di Rende (Cs) ITALY Tel: +39 (0)984 473428 cell: +39 349 4241367 Email: lucakreek@libero.it