- EN
When sizing medium & low-temperature parallel rack systems, many refrigeration engineers immediately turn to screw compressors. But for cold storage and centralized supermarket refrigeration with fluctuating heat loads, the Frascold Z-series 6-cylinder semi-hermetic piston compressor, specifically the Z35-106Y, stands out as a practical, field-proven alternative. It is not a newly launched fancy product; it is a mature workhorse validated across hundreds of refrigeration projects globally.
Z35-106Y is a 6-cylinder semi-hermetic reciprocating compressor from Frascold standard Z series, rated at 35HP (shaft power approx. 26 kW). Its displacement reaches 106.16 m³/h at 50Hz and 127.39 m³/h at 60Hz. Net weight is 223 kg, motor terminal box with IP65 protection, charged with 3.7 L POE68 refrigeration oil.
It works with traditional HFC refrigerants such as R404A, R507, R134a, and is also compatible with low-GWP refrigerants R448A, R449A. VFD modification is available, operating frequency range 30~70Hz. Variable frequency operation is a non-standard application and must be verified via FSS3 software and approved by Frascold. It is suitable for food freezing rooms, supermarket centralized refrigeration, process cooling and ice cream production lines.
Screw compressors deliver high COP under full load. However, real cold room loads are rarely constant. Heat load spikes during goods loading, then drops sharply overnight when only insulation loss remains. Most small & medium parallel cold rooms operate under partial load (50–70%) for most of the year.
Equipped with optional RSH capacity control head, Z35-106Y provides stepped unloading. When cooling demand reduces, the compressor unloads step by step instead of frequent on-off cycling. This cuts motor starting surges and reduces energy waste. In multi-unit parallel racks, combining multiple Z35-106Y units plus individual capacity unloading creates smooth stepped cooling capacity matching variable heat loads — a clear operational advantage for food cold rooms with intermittent stock intake.
Thanks to optimized mechanical balance, the 6-cylinder design delivers lower vibration and quieter operation compared with 4-cylinder models of equivalent power. Semi-hermetic construction integrates motor and compression assembly. Cylinder heads and valve plates can be serviced on-site without shaft seal maintenance required for open-type compressors, which makes field maintenance easier for local refrigeration teams.
✅ Recommended: Food freezing cold rooms, supermarket centralized refrigeration, food process cooling, multi-compressor parallel racks with large day-night load swing, compact machine room with on-site maintenance requirement.
Frascold Z35-106Y is not designed to replace screw compressors, but to serve as a complementary solution for medium/low-temperature parallel racks with fluctuating loads. Its core strengths lie in proven 6-cylinder mechanical design, RSH stepped unloading, wide refrigerant compatibility and service-friendly semi-hermetic structure. With the global shift toward low-GWP refrigerants and stricter energy control, more refrigeration contractors are re-evaluating this classic piston compressor..
