Highly effective and proven on many installations, corrosion inhibitor and hardness stabilizer containing oxygen binding agents for hot and warm water and district heating systems. The formulation effectively removes boiler scale. It is an alkaline concentrate based on tannins with additional hardness-binding agents in aqueous solution. The product is physiologically and toxicologically safe. Not volatile in vapors - Also acceptable in hospitals and the food industry. The advantage is the rapid removal of corrosive oxygen and the stabilization and dispersion of insoluble salts. The product is designed for contaminated systems with difficult feed water quality. Forms a dynamic, non-inhibiting heat transfer film of iron tannin that creates corrosion protection on the metal Gently removes existing deposits through surfactant additives. The rate of action depends on the specific sediment composition and operating conditions.