Wow, Thanks for the thorough reply! In the IBD distillation studies they note 20C as the desired distillate output temp, but don't explain why. I assumed it is because valuable congeners might evaporate if the temp is too high, but just may be because of safety concerns (like you explain). In the cognac tradition they also talk about optimal distillate temperature in terms of spirit profile outcome. See for example this tech note from the Germain Robin distillery:
Hey, It is widely accepted that distillate should be collected straight off the condenser at 15-20°C (60-70°F). My problem is that the water coming out my tap are usually around 30°C (85°F), so there is no way I can bring the distillate down to the desired temperature. What is the best (and least expensive) method of bringing the water temperature down before it reaches the condenser? My setup includes two alembic stills: 250L and 1,000L. Thanks!