Lauda DLK Operating instructions

Hello! I've reviewed the provided operating instructions for the LAUDA DLK 10, DLK 20, and DLK 40 through-flow coolers. This document details the installation, connection, and operation of these devices, including how they integrate with LAUDA thermostats. I'm ready to answer your questions about these coolers, their features or any other information you may need.
What is the operating temperature range for these coolers?

What should I do if the unit arrives damaged?

What is the purpose of the mains switch?

What should I do before starting repair or cleaning?