Lauda KR Operating instructions

Hello! I'm your AI assistant, and I've reviewed the user manual for the LAUDA K-4/R and K-4/RD circulators. This document details how to properly use and maintain this device. It includes information on temperature control, external circulation, and troubleshooting common issues. I can help you answer your questions about the circulator and its components.
What should I do if the mercury column in the thermoregulator is separated?

How long should I wait before turning the compressor back on after switching it off?

What is the purpose of connecting a short piece of hose across nozzles 20 and 21?