Calculate actual and target superheat for AC and refrigeration systems. Supports R-410A, R-32, R-454B, R-404A, R-22 and more. Includes charging charts.
Calculate actual subcooling at the condenser outlet. Verify against target subcooling for proper refrigerant charge. Covers all major refrigerants.
Convert between refrigerant saturation pressure and temperature for R-410A, R-32, R-454B, R-22, R-134a, R-404A, R-407C and more.
Full pressure-temperature saturation lookup for all common refrigerants. Faster than a paper PT chart in the field.
Calculate required refrigerant charge by line set length, indoor unit size, and manufacturer specifications for non-standard installations.
Calculate total refrigerant charge from line set volumes, component internal volume, and liquid/vapour density segment by segment.
Look up thermodynamic properties of common refrigerants at any temperature or pressure. Enthalpy, density, specific heat, and latent heat.
Convert refrigerant charge quantities between refrigerants for retrofit projects, plus unit conversions between kg, lb, and oz.
Compare any two refrigerants side by side: GWP, safety class, operating pressures, capacity, and efficiency. R-410A vs R-454B and more.
Calculate blended GWP, temperature glide, bubble/dew point, and safety class for zeotropic blends like R-407C, R-448A, and R-454B.
Check compatibility between refrigerants and lubricants: POE, PAG, alkylbenzene, and mineral oil. Includes retrofit flush guidance.
Calculate CO2-equivalent emissions from refrigerant charge, annual leak rate, and end-of-life scenarios. Compare up to 4 refrigerants.
Track HFC phase-down schedules under Canada's HFC Regulations and the Kigali Amendment for R-410A, R-404A, and R-22 systems.
Estimate refrigerant leak rates and annual loss from low charge symptoms. Calculate GWP-weighted emissions from ongoing leaks.
Calculate refrigerant quantity remaining in cylinders by weight. Determine if sufficient charge is available for a job.
Estimate recovery time, required cylinders, and residual pressure for push-pull, vapour, and liquid recovery methods.
Size suction, discharge, and liquid lines. Calculates velocity, pressure drop, and recommends ACR copper pipe sizes.
Plot refrigeration cycle state points on a P-H diagram. Calculate refrigerating effect, work of compression, and COP.
Calculate duty, LMTD, and required surface area for plate and shell-and-tube heat exchangers in refrigeration circuits.
Check both subcooling and superheat together in one pass to diagnose charge level and airflow issues in a single reading.
Calculate Coefficient of Performance for refrigeration and heat pump cycles. Compare actual vs. Carnot COP.
Calculate actual refrigerating capacity from field-measured pressures and temperatures. Compare against nameplate rating.
Convert suction pressure to evaporating temperature or find target pressure for a desired evaporating temperature.
Convert discharge pressure to condensing temperature. Calculates subcooling and condenser approach temperature.
Calculate compression ratio from suction and discharge pressures. Assesses if two-stage compression is needed.
Calculate optimal intermediate pressure, intercooler temperature, and power savings for two-stage compression.
Size flash tank intercoolers for two-stage systems. Calculates flash fraction, vapour quality, and vessel diameter.
Calculate capacity boost, sub-cooling gain, and COP improvement for vapour-injection economizer cycles.
Calculate AC and heat pump performance at low outdoor ambient. Determine capacity de-rating and required head pressure controls.
Size evaporator coils from refrigeration load, temperature difference (TD), and refrigerant. Calculate required coil area and airflow.
Size air-cooled and water-cooled condensers from total heat of rejection (THR). Calculate condenser TD and airflow.
Size thermostatic and electronic expansion valves from system capacity and refrigerant. Verify pressure drop and hunting risk.
Calculate required compressor capacity from evaporating and condensing temperatures, compression ratio, and displacement.
Calculate isentropic and volumetric efficiency, actual vs theoretical power, from field-measured pressures and power.
Size oil separators for refrigeration systems. Calculates required vessel diameter, gas velocity, and oil return rate.
Calculate total heat of rejection at the condenser from system capacity and COP. Used for condenser sizing.
Calculate defrost heat load, cycle duration, and energy use for electric, hot gas, and off-cycle defrost systems.
Calculate total refrigeration load for walk-in coolers and freezers: transmission, infiltration, product, and internal heat.
Calculate refrigeration load for produce, dairy, and floral cold rooms including product respiration heat.
Calculate walk-in and blast freezer heat load including product freezing load and latent heat of fusion.
Calculate pull-down time, peak load, and required capacity to cool a room or freeze a product batch to setpoint.
About Refrigeration Calculations
Refrigeration calculations are essential for proper system diagnosis, charging, and design. The vapour compression refrigeration cycle involves four key processes — compression, condensation, expansion, and evaporation — each with specific performance metrics that must be within specified ranges for efficient and reliable operation.
Key Refrigeration Concepts
- Superheat: The temperature of refrigerant vapour above its saturation temperature at a given pressure. Target superheat at the evaporator outlet is typically 4–7°C (8–12°F). Use the Superheat Calculator.
- Subcooling: The temperature of liquid refrigerant below its saturation temperature at a given pressure. Target subcooling at the condenser outlet is typically 5–8°C (10–15°F). Use the Subcooling Calculator.
- COP: Coefficient of Performance — the ratio of useful refrigerating effect to work input. Higher COP means a more efficient system. Use the COP Calculator.
- Refrigerant Transitions: With R-22 phaseout complete and R-410A being replaced by A2L refrigerants (R-32, R-454B), the Refrigerant Conversion Calculator and Refrigerant Comparison Calculator help navigate alternatives.
Related Tools
Refrigeration analysis connects closely with psychrometrics for air-side analysis, cooling load calculations for system sizing, and SEER calculations for efficiency rating. The SHR calculator helps match equipment to space moisture conditions.
Frequently Asked Questions
Superheat is the temperature of refrigerant vapour above its saturation temperature at a given pressure, typically measured at the evaporator outlet or compressor suction. Subcooling is the temperature of liquid refrigerant below its saturation temperature, typically measured at the condenser outlet. Both are used together to verify correct refrigerant charge — use the Subcool / Superheat Combo Calculator to check both at once.
Refrigerant charge is calculated from line set length, indoor and outdoor unit specifications, and manufacturer charge tables using the Refrigerant Charge Calculator or the Charge Weight Calculator for segment-by-segment volume calculations, then verified in the field using superheat (fixed orifice systems) or subcooling (TXV systems) measurements against target values.
R-410A is being phased down in favour of lower-GWP A2L refrigerants including R-32 and R-454B. R-404A in commercial refrigeration is being replaced by R-448A and R-449A. Check the Refrigerant Phase-Out Guide and Refrigerant Comparison Calculator for details on Canada's HFC Regulations and Kigali Amendment timelines.
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