HVAC Calculators
Calculate fan laws, duct static pressure, BTU recovery, and gas piping capacities for mechanical systems.
ACCA Manual J Residential Heat Load Calculator
Perform verified block heating and cooling load calculations per ANSI/ACCA 2 Manual J (8th Edition). Accurately size heat loss, sensible/latent heat gain, and equipment tonnage.
Air Changes per Hour (ACH) Calculator
Calculate required fan CFM to achieve target air changes (ACH) for residential or commercial ventilation systems per ASHRAE 62.1 and IMC 2024.
Boiler Surface Blowdown Rate
Calculate boiler surface blowdown rate to control dissolved solids, prevent scale formation and steam carryover. Includes cycles of concentration formula, TDS limits by operating pressure, and blowdown heat recovery economics.
Boiler Make-Up Water & Valve Sizing
Calculate the required GPM auto-fill rate and PRV valve sizing for hydronic heating systems based on boiler BTUH rating and loop pressure. Includes cold-fill PSI guidance, expansion tank relationship, and valve selection by flow capacity.
Centrifugal Fan Brake Horsepower (BHP) Calculator
Calculate the raw aerodynamic horsepower required at the fan shaft to overcome duct static pressure before factoring in electrical drive losses.
Chiller Efficiency Converter (COP / EER / kW-ton)
Bi-directional standardized thermodynamic conversion for industrial chiller efficiency indexes, decoding exactly how much electrical grid load is drawn per physical refrigeration ton.
Commercial Chiller IPLV Calculator
Calculate Integrated Part Load Value (IPLV) and Non-Standard Part Load Value (NPLV) for commercial chillers per AHRI Standard 550/590 and ASHRAE 90.1.
Compressor Volumetric Efficiency Engine
Calculate the true volumetric pumping efficiency of a reciprocating HVAC/R compressor based on clearance volume and compression ratios to diagnose severe systemic failures.
Cooling Coil Condensate Engine
Exactly calculate the gallons per hour of destructive condensate water stripped from the airstream across a cooling coil based on psychrometric humidity drops and mass airflow tracking.
Cooling Tower Approach & Range Efficiency
Analyze thermodynamic evaporative efficiency, Range, and Approach temperature of commercial cooling towers per CTI ATC-105 and ASHRAE 90.1 standards.
Cooling Tower Makeup & Blowdown Engine
Calculate commercial cooling tower evaporation rates, chemical blowdown requirements, and total makeup water demand using the 0.03 GPM/Ton approximation rule for chiller plant sizing.
Hydraulic Pipe Friction (Darcy-Weisbach)
Execute rigorous Darcy-Weisbach head loss equations to determine exact dynamic pipe friction vectors across complex commercial hydronic networks and chilled water loops.
Dew Point & Condensation Analyzer
Mathematically calculate the exact threshold where atmospheric humidity turns into liquid water using the Magnus-Tetens risk equation to prevent structural rot.
HVAC Duct Equivalent Length Calculator
Mathematically calculate aerodynamic friction and structural turbulence loss across sheet metal HVAC elbows translating them into straight-pipe equivalent lengths.
HVAC Duct TEL & Static Friction Loss Calculator
Calculate Total Equivalent Length (TEL) and resulting external static pressure drops by mathematically compounding the aerodynamic drag of straight pipe with high-friction HVAC elbows and terminal boots.
HVAC Available Friction Rate Estimator (Manual D)
Determine the target Friction Rate (FR) for sheet metal sizing by calculating Total External Static Pressure (TESP) deductions against the Critical Path Equivalent Length.
HVAC Duct Transition & Reducer Fabrication Calculator
Mathematically determine the minimum SMACNA-compliant fabrication length required for sheet metal duct transitions to prevent high-velocity aerodynamic stall and turbulence.
HVAC Sheet Metal Duct Weight Calculator
Calculate HVAC sheet metal duct weight for structural support design from dimensions and gauge per SMACNA standards.
HVAC True Cooling Load: Total Defrost & Enthalpy
Exactly calculate the total thermodynamic heat removal (BTU/hr) and system Tonnage based on the combined sensible (temperature) and latent (moisture) energy state of the air.
Evaporative Cooler Sizing
Calculate the exact CFM requirements for evaporative coolers based on home volume, arid climate constraints, and mandatory air-change rates.
Hydronic Expansion Tank Volume Sizing
Calculate required acceptance and total volume for closed-loop hydronic expansion tanks per ASME Section VIII and ASHRAE design standards.
HVAC Fan Laws Calculator (Affinity Laws)
Exactly calculate the aerodynamic consequences of altering blower RPM. Predict the new exponential required Brake Horsepower, CFM, and duct Static Pressure before switching pulleys.
Gas Pipe Pressure Drop Sizing (Pole's Formula)
Verify IFGC friction boundaries for low-pressure black iron natural gas and propane distribution lines. Prevent flame roll-outs and burner starvation.
Geothermal Ground Loop Sizing Calculator
Determine exact excavation bore depths and required total HDPE pipe lengths needed to successfully sink heat pump refrigerants into stable earth loops without thermal saturation.
Room CFM & Duct Sizing Estimator
Estimate required HVAC airflow (CFM) based on room volume and Air Changes per Hour (ACH), and map it to a strictly sized residential round duct.
Hydronic Baseboard Radiation Sizing Calculator
Size standard fin-tube baseboard radiation for residential boiler systems. Calculate the required linear footage mathematically based on room BTU heat loss, target water temperature, and pump GPM flow rate.
Hydronic Buffer Tank Sizing Calculator
Calculate hydronic buffer tank thermal storage volume to prevent boiler and heat pump short-cycling per ASHRAE and Caleffi engineering design standards.
Commercial Kitchen Hood CFM Calculator
Mathematically calculate IMC-compliant minimum exhaust CFM for commercial kitchen hoods based on duty classification, architectural hood style, and physical hood dimensions.
Langelier Saturation Index (LSI) Calculator
Mathematically verify water chemistry equilibrium. Calculate LSI to predict if your hydronic system or pool is actively dissolving copper (corrosive) or depositing destructive calcium scale.
HVAC Line Set Trim Charge Calculator
Mathematically calculate the exact ounces of additional R-410A required for long refrigerant line sets exceeding factory allowances. Essential for preventing compressor flood-back and maintaining target subcooling.
Log Mean Temperature Difference (LMTD) Calculator
Mathematically calculate the exact Logarithmic Mean Temperature Difference (LMTD) driving force for counter-flow and parallel-flow shell-and-tube or plate heat exchangers.
Make-Up Air (MUA) Heating Load Calculator
Mathematically calculate the extreme sensible heating capacity (BTU/hr) required to temper frigid winter Make-Up Air for commercial kitchen exhaust hoods.
Mini-Split BTU Load Estimator
Mathematically estimate the required cooling minimums (BTUs and Tonnage) for ductless mini-split HVAC zones based on footprint, solar gain, and metabolic loads.
Mixed Air Temperature (MAT) Calculator
Mathematically resolve psychological air mass enthalpy by calculating the exact Mixed Air Temperature (MAT) created when indoor RETURN air rapidly blends with outdoor MAKEUP air.
Moist Air Enthalpy Calculator
Calculate specific enthalpy of moist air, decomposing sensible and latent heat components per ASHRAE psychrometric formulations.
Pitot Tube Traverse Calculator
Mathematically execute a 16-point Pitot Tube Traverse matrix by correctly averaging the square roots of Velocity Pressures (VP) to isolate True Average FPM and Absolute Duct CFM.
Psychrometric State Point Calculator
Calculate relative humidity, dew point, and humidity ratio from dry-bulb and wet-bulb temperatures using ASHRAE psychrometric formulations.
HVAC Blower Pulley Speed & Sizing Calculator
Calculate motor pulley drive ratios, belt RPMs, and driven blower sheave sizing to target required HVAC airflow per AMCA Standard 203.
Pump Affirmity Laws Calculator
Mathematically project Variable Frequency Drive (VFD) energy savings by isolating the cubic brake horsepower reduction parameters governed by centrifugal Pump Affinity Laws.
Pump Affinity
Apply Pump Affinity Laws to predict flow, head, and power changes at any new speed or impeller diameter.
Refrigerant Line Set Charge Adder Calculator
Calculate exactly how many ounces of additional refrigerant must be weighed into a split-system air conditioner or heat pump when the physical copper line set exceeds the factory pre-charge baseline distance.
SMACNA Duct Leakage
Evaluate duct static pressure class, leakage rate thresholds, and air loss percentages compliant with SMACNA HVAC Air Duct Leakage Test standards.
Steam Pipe Warm Up Condensate Load
Calculate the massive thermodynamic condensate surge produced when live steam contacts cold inactive steel piping during startup, and properly size drip-leg traps to prevent catastrophic water hammer.
Superheat Subcooling Diagnostic
Diagnose refrigerant charge accuracy by calculating Total Superheat (fixed-orifice systems) and Total Subcooling (TXV systems) from live manifold gauge pressures and thermocouple line temperatures.
Commercial Ventilation ACH & Louver Calculator
Calculate required exhaust fan CFM from room volume and Air Changes per Hour (ACH), then size the makeup air intake louver free-area per AMCA 500-L and IMC standards.