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No. 340 Scale Inhibitor

  • Prevents scale in cooling towers and evaporative condensers
  • Freeze proof to -10ºF
  • Excellent in extremely hard and high alkalinity water


No. 340 Liquid Scale Inhibitor is an organic product based upon AMP phosphonate. It is formulated for preventing scale in cooling towers and evaporative condensers. It is extremely effective, particularly when the water is extremely hard and high in alkalinity. No. 340 is stable and there is no breakdown up to the boiling point, even in highly alkaline or acid solutions. In addition, it is freeze proofed to -10ºF and is most effective and economical at treatment levels of 12–15 parts per million (about 1 gallon per 100,000 gallons of water).

Cooling towers and evaporative condensers can be troubled with scale formation where the water is hard and high in alkalinity. This scale can form on condenser surfaces, piping, valves and tower fill. And when it does, water flow and heat transfer are reduced, head pressures go up, power is wasted and a costly motor burnout can result. Treatment with No. 340 can prevent these problems.

Packaging Size Part Number Additional Info
1 Gallon Bottle 4340-08
5 Gallon Pail 4340-05


Generally in hard alkaline waters, a feed rate of 1/2 gallon per month is recommended for each 30 tons with a bleed-off rate of 1 gallon per minute. A continuous, accurate feed can be accomplished with either the No. 215 or No. 1075 Drip Feeder on systems up to 150 tons. This capillary action plastic tubing can be adjusted to control the flow rate and is easily maintained. For larger systems No. 340 Liquid Scale Inhibitor can be fed with the CMS Feed Pump, or the more complete CMS-IV Cooling Monitor System.

Detailed instructions can be found on product bulletin 3-12. (Download by clicking on the "Product Information" tab.)

No. 340 Liquid Scale Inhibitor should be maintained at 12-15 ppm in the recirculating water. The K1583 or No. 89A Test Kit (4798-2) provide the necessary testing procedure.

Product Information:

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RTK Information

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