• Four parameters that decide chiller selection

  Temperature range, cooling capacity, circulation flow and head, and condensing method. Get these four right and selection rarely goes wrong. This article works through each using catalogue data.

• Cascade refrigeration: how a chiller reaches -110℃

  Single-stage vapour compression struggles below -60℃. The PTLD series uses a cascade design — R404A on stage one with R23 or R508B on stage two — to hold medium temperature down to -110℃.

• Reading a GPTECH model designation

  What does each character in DLS—B0.5WN mean? Series, temperature band, capacity, condensing method and non-standard code — the naming logic across all four families.