Thermo Scientific Precision Guide De Démarrage Rapide page 49

Chapter 3
| Installation
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.
Thermal Beads
GP baths can use thermal beads. The beads replace water to reduce the risk of contamination.
When using the beads allow the bath to equilibrate overnight, the temperature might rise 10°C or
more above the set point during equilibration. Another option is heat up the bath for ten minutes
then stir the beads with a stir rod. Allow two to five hours to equilibrate.
Note Thermal beads will degrade the bath's uniformity and stability.
3-4
| Precision Thermo Scientific