Refrigeration System
Square designs and builds industrial refrigeration skids, ASME and PED pressure vessels, condensers, pump circulation packages, and PLC control panels for food plants and cold stores worldwide.
Built for natural refrigerants (NH3 and CO2) or synthetic refrigerants, our skids pair MYCOM, BITZER, and KOBELCO compressors with Danfoss, Emerson, and Parker valves on steel frames tested in our own factory.
Global screw and piston compressors (MYCOM, BITZER, KOBELCO)
ASME (U and U2) and PED pressure vessels built in our own plant with 100% X-ray weld checks
Automated PLC and SCADA compressor staging, VFD part load control, and safety interlocks

Product Features
Why Choose Square's Refrigeration System
ASME and PED pressure vessels built in our own factory, natural refrigerant design, and global compressor brands.

Factory ASME & PED Pressure Vessel Manufacturing
We build all oil separators, liquid receivers, intercoolers, and surge drums in our own plant using ASME welders, plasma welding, and X-ray inspection to meet ASME and PED codes.

Turnkey Refrigeration Engineering
Full cooling engineering from heat load sizing, P&ID drawings, and skid building to site piping, startup, and operator safety training.

Tier One Global Components
We build our skids with MYCOM, BITZER, and KOBELCO compressors plus Danfoss, Emerson, and Parker valves so spare parts are easy to get worldwide.

Product Structure
- Factory built steel compressor skids combining screw or piston compressors, oil separators, oil coolers, receivers, and valve stations.
- Built for pumped ammonia (NH3), transcritical CO2, NH3 and CO2 cascade, or HFC circuits.
- PLC controller stages compressors, condensers, oil return, and defrost while logging pressures and temperatures.

System Advantages
- Integrated hot gas or electric defrost sequencing coordinated with freezer operation.
- Automated oil management, liquid level regulation, and dual pressure relief valve manifolds.
- Preformed piping with minimal brazed joints, factory pressure tested and helium leak checked prior to shipment.
- ASME (U/U2) and PED certification available for all pressure vessels.
Technical Specifications
Parameters
Standard specifications are listed below. We size compressors, refrigerants, pressure vessels, heat recovery, and PLC controls for your plant.
| Compressor type | Open drive reciprocating / Screw (single and twin) |
|---|---|
| Refrigerants | NH₃ (R717) / CO₂ (R744) / Cascade NH₃-CO₂ |
| Evaporating temperature | −45°C to +10°C |
| Condensing temperature | +25°C to +45°C (ambient dependent) |
| System capacity | 50 kW to 5+ MW per system |
| Condenser type | Evaporative / Air cooled / Shell and tube (water cooled) |
| Oil system | Oil separator, oil cooler, oil management system |
| Controls | PLC with SCADA, compressor sequencing, remote monitoring |
| Safety | Gas detection, emergency ventilation, relief system per EN 378/IIAR |
| Heat recovery | Optional: desuperheater for hot water, oil cooling heat reclaim |
| Installation | Factory assembled skids or field erected |
| Typical lead time | 16 to 22 weeks (custom built system) |
| Design life | 25+ years (pressure vessels); 20+ years (compressors with maintenance) |
Design Details
How Each Subsystem Is Engineered
Open each section below to see how key parts of the system work.
NH₃ vs. CO₂ Refrigerant Selection
NH3 (Ammonia, R717): The top natural refrigerant for medium and large freezing plants. It has zero ODP, zero GWP, low cost, and the highest cooling efficiency. Built with full EN 378 and IIAR gas detection, ventilation, and relief valves.
CO2 (R744): A nontoxic, nonflammable (A1) natural refrigerant with a GWP of 1 and strong low temperature capacity. Ideal for food halls and sites where ammonia charge is limited.
NH3 and CO2 Cascade: Keeps a small ammonia charge inside the machine room while circulating safe CO2 through process freezers and cold rooms.
Compressor Technology & Part Load Efficiency
Square selects compressor type based on your capacity and operating conditions:
- Screw compressors: 200 kW to 2+ MW per unit. Variable Vi (built in volume ratio) maintains efficiency at part load. Ideal for medium to large systems with varying loads.
- Reciprocating compressors: 50 to 300 kW per unit. Excellent part load efficiency via cylinder unloading. Ideal for smaller systems or where load varies widely.
For facilities with variable production, we configure compressor sequencing and VFD control to maintain efficiency across the full operating range, not just at design conditions.
Heat Recovery & Energy Integration
Industrial refrigeration systems reject large amounts of heat through the condenser. Much of this heat can be recovered:
- Desuperheater: recovers high grade heat from compressor discharge gas (70 to 90°C) for facility hot water
- Oil cooling heat reclaim: compressor oil cooling heat used for underfloor heating or preheating
- Condenser heat: lower grade heat (25 to 35°C) usable for space heating or defrost water preheating
- Typical energy savings: 15 to 30% reduction in facility heating costs
Safety Systems & Regulatory Compliance
Ammonia systems include full safety controls built to EN 378 and ASHRAE 15 / IIAR rules:
- Gas sensors trigger a warning at 25 ppm and start emergency fans at 150 ppm
- Emergency machine room fans rated for 30 air changes per hour
- Dual pressure relief valves piped to a safe discharge point
- Emergency stop buttons outside the room and automatic high gas shutdown
- Gas tight machine room doors and external electrical switches
Installation & Commissioning
Square handles site installation and startup:
- Factory wired skids cut site piping and wiring work by 40% to 60%
- Installed by our 200+ field engineers or your supervised local crew
- Full pressure testing, vacuum evacuation, and refrigerant charging
- Cold test runs at design load
- Hands on operator safety and maintenance training
- Complete P&ID drawings, wiring diagrams, and safety manuals
Proven in These Food Applications

Process Freezer Refrigeration Plants
Supplies pump recirculated NH₃, CO₂, or cascade refrigeration at −35°C to −45°C for spiral, tunnel, fluidized bed, and plate freezers.

Cold Chain Logistics & Refrigerated Docks
Keeps temperature and humidity steady across cold loading docks, staging halls, and distribution centers.

Multiple Temperature Cold Storage Warehouses
Centralized multiple compressor racks serving high bay frozen storage (−25°C), chilled rooms (+2°C), and blast freezing cells.
Case Studies
Refrigeration System in Operation Worldwide
Proven installations running in food plants around the world.
Frequently Asked Questions
Every Square skid is built on a heavy steel frame using MYCOM, BITZER, or KOBELCO compressors, ASME and PED vessels with 100% X-ray weld checks, and PLC safety controls.
We use industrial screw and piston compressors from MYCOM, BITZER, and KOBELCO paired with Danfoss, Emerson, and Parker valves for easy global service.
Square holds ISO 9001, ISO 45001, CE, PED, ASME (U and U2 stamps), EAC, CSA, CRN, and CNAS laboratory accreditation, supported by 300+ patents, 300+ R&D engineers, and 300+ installation and service engineers.
We engineer custom industrial refrigeration packages, tailoring skid layout, cooling capacity, refrigerant selection (Ammonia, CO2 cascade, or Freon), ASME/PED pressure vessels, and PLC control logic to your project requirements.
Our engineers review your cooling load, target temperatures, local safety rules, and power rates to recommend the best ammonia, CO2, cascade, or HFC system.
Engineering Inquiry
Discuss Your Refrigeration System Project
Share your cooling load and refrigerant preference for a refrigeration system quote.










