Nu-Calgon - For spraying coil cleaners such as Nu-Brite®, CalClean®, HD CalClean®, Alka-Brite® Plus, Tri-Pow'r® HD or any of the other quality Nu-Calgon coil cleaners for cleaning air cooled condensers, evaporator coils, etc. No pre-mixing is necessary as chemical and water are automatically blended in mixing head as you spray. Use for coil cleaning as well as in food preparation areas, wash rooms, or any situation where use of water-diluted chemicals are required. Recommended water pressure 40 to 60 psi, although 40 - 90 is acceptable.