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HVAC Waters
     

preoperational cleaning
       
Alkaline Flush & Rinse
Follow manufacturers' procedures for cleaning package equipment such as boilers and chillers.

Even the cleanest of fabrications requires preoperational cleaning, which removes normal construction contaminants - temporary protective coatings, weld slag, grease, oil and dirt.

A hot, system-wide, pH 11, alkaline flush is the method of choice for closed heated water and chilled water loops.

Recipe
chemical (Do not mix in aluminum containers.) 

ounces per 100 gallons of system water 
TSP (trisodium phosphate)      16
Lye   (sodium hydroxide)      1
Dawn      (liquid surfactant)   1
sodium sulfite  (oxygen scavenger) 1

Cleaning
Add chemicals to the system one-at-a-time in the above ratios via the system's pot feeder until pH 11 is reached. (Do not use portable aluminum pressure feeder.) Circulate water at operating temperature in all zones for 6 to 24 hours.

Rinsing
Concurrently drain & make-up with raw water until pH is reduced to 7.5.