Loop seal purpose

I directed the maintenance crew to disassemble and clean the drain lines from both the final condenser (B), and the primary jet discharge condenser (A). Unfortunately, they failed to reassemble the loop seal from condenser A. But what is the purpose of this loop seal ... 

Pressure-sensitive adhesives (PSAs) based on acrylic, natural rubber and silicone are employed primarily for ease of application. To name Just a few applications, PSAs bond decals to surfaces, interior decorative surfaces to interior panels, interior trim pieces in place directly or hook and loop tape for the same purpose, structural shims in place during manufacturing and acoustic (sound deadening) materials to body skin interior surfaces. Tape products with pressure-sensitive adhesive on one or both surfaces are used for such functions as cargo compartment sealing, as a fluid barrier to prevent spills and leaks in the lavatories and... 

The HV-module consists of transformer, voltage doubler, filtering network and feedback resistor chain, and is sealed so that no humidity can reach the components. If for any reason the feedback loop is interrupted, an over-voltage detection is activated and shuts down the instrument. For test purposes, it is necessary to disconnect (or remove) diode CR109. 

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