Thermo Scientific Precision Water Bath User Manual page 47

Section 3 | Installation
To help alleviate bacteria or algae growth Thermo Fisher Scientific recommends the use of small
amounts of chlorine. The usage of chlorine needs to be monitored over time in order to prevent
the formation of corrosion.
The duration of time that chlorine remains in solution depends on factors such as water
temperature, pH and availability of direct sunlight. We recommend maintaining chlorine levels at
1 to 5 ppm free chlorine. PPM levels can be monitored using standard water quality test strips.
For best results, maintain the pH of the fluid between 6.5 and 7.5.
Do not add additional chlorine without first determining the concentration ratio that already exists
in the fluid supply. Corrosion and degradation of the circulation components can result from
concentration ratios that are too high. Contact our customer support for additional information.
De-ionized Water
De-ionized water is water that has had its mineral ions removed using ion exchange resins. The
purpose of this process is to remove the ions that allow electrical current to flow more easily
through water. This helps to prevent electrical leaks to ground through the recirculating fluid.
De-ionized water is in an unbalanced state and will leach the missing ions from the materials
it comes in contact with. The aggressive nature of this leaching can cause pitting on metal
surfaces. Note that the de-ionizing process does not remove microorganisms. Because of this, we
recommend de-ionized water only with applications that have it as a specified requirement. In any
case, only de-ionized water with 1 MΩ-cm resistivity, or less, is recommended.
Recommended Biocides and Inhibitors
Thermo Fisher Scientific offers a biocide and inhibitor package Thermo 200 (Nalco) premixed with
five gallons of water or as a kit to be added to water.
Biocides are corrosive and can cause irreversible eye damage and skin burns.
WARNING
They are harmful if inhaled, swallowed or absorbed through the skin. Refer to the
manufacturer's most current SDS.
3-4 | Precision
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