Water treatment for HVAC&R systems encompass both open recirrculating cooling water systems and closed systems. Open recirculating cooling systems reject heat through cooling towers. Closed systems can be either cooling or hot water systems. These systems convey chilled or hot water to areas that require cooling or heating.

Article appeared in the Practical Guide to Water Treatment, which was included with the vol. 41, no. 5, May 1999 issue.