BINDER KB 23 - Manual (Page 70)

KB (E3.1 + E5.1) 11/2014 page 70/100
15. Defrosting during refrigerating operation
BINDER cooling incubators are very diffusion-proof. To ensure high temperature precision there is no
automatic cyclic defrosting device. The DCT™ refrigerating system largely avoids icing of the evaporation
plates. However, at very low temperatures the moisture in the air can condense on the evaporator plates
leading to icing.
Always close the door properly.
• Operation with temperature set-points above +5 °C / 41 °F at an ambient temperature of 25 °C /
77 °F:
The air defrosts the ice cover automatically. Defrosting is continually performed.
• Operation with temperature set-points below +5 °C / 41 °F:
Icing on the evaporator is possible. Defrost the unit manually.
With temperature set-points < +5 °C / 41 °F, regularly defrost the unit manually:
•
Set the temperature to 40 °C / 104 °F (in Fixed value entry mode)
• Let the unit operate for about 30 minutes with the door closed.
Excessive frosting of the evaporator is indicated by reduced refrigerating performance.
KB 23: Cooling power decreases when the fan speed is reduced to 20% or below.
• Operation with temperature set-points below 0 °C / 32 °F (KB from size 53 on):
While operating the KB with set-points below < 0 °C / 32°F condensation is possible at the inner
surface of the door around the door gasket.
In case of heavy condensation, check tightness of the door gasket.
After one or two days operation at a set-point < 0 °C / 32 °F a thin ice layer can cover the inner unit
door and the glass door. The amount depends of the ambient temperature and humidity. This does not
influence the proper function of the refrigerating system.
Refrigerating performance decreases while operating the chamber at temperatures < 0 °C
/ 32 °F due to icing of the evaporators. For this reason defrost the chamber regularly, e.g.
once a week.