Chiller Free-Cooling
The cooling system uses a thermosiphon
cycle to produce cooling without
using compressors when outdoor
temperatures are under 10°F (–12°C).
This is a definite innovation for energy
efficiency considering 844 hours
occurring below 10°F (–12°C) on a
normalized Quebec City weather file.
The warehouse chiller is also used to produce cooling for the
office areas. To maximize energy efficiency in cooling the offices,
the chiller has two different pressure inputs to produce
two different temperatures: 26°F (2°C) for the office area
and 12°F (–11°C) for the warehouse. The left half of Figure
2 shows the normal operation cycle. The right half shows the
thermosiphon cooling principle.