 This study will evaluate the tolerability and safety of valsartan in patients with stable, chronic heart failure NYHA Class ll-lll. The 12-week double blind study has a 2-week maximum screening, and a 10-week active treatment phase. In each of the treatment arms QD and BID, patients are up-titrated to a maximum valsartan total daily dose of 320 mg. Patients remain on their prior CHF standard care therapy throughout the study period, and the up-titration of valsartan is based on patient tolerability. 