The design of the Multicolumn Thermostat (MCT) uses Quick Connect Heat Exchangers that are mounted on to the heating and cooling devices with Peltier elements. The solvent entering the Quick Connect Heat Exchangers is heated up or cooled down to a settable temperature before entering the column. A triangular shape of the Quick Connect Heat Exchangers prevents incorrect placement and ensures optimum heat exchange of the solvent. Optimal insulation of the heater room offers best temperature stability for the column. This ensures that the column and the solvent flowing through it are almost at the same temperature. The solvent cools down or heats up on its transfer from the Quick Connect Heat Exchangers to the column inlet. This depends on several factors: flow rate, setpoint temperature, and ambient temperature. Any type of heated column compartment brings one important consequence for column temperature equilibration. Before an equilibrium is reached, the whole mass of column, column packing, and solvent volume inside the column has to be brought to the selected temperature. This depends on several factors: flow rate, setpoint temperature, ambient temperature, and column dimensions. The column equilibrates faster at higher flow rates (due to thermostatted mobile phase). In a flowthrough temperature regulation system, there are necessarily slightly different temperatures at different positions. The actual temperature displayed on the user interface is always the temperature measured at the heating and cooling device.
The equilibration of the column may take a while. Stability of the pressure signal is a good indication for temperature equilibrium of the column.
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id: 3002304523