HVAC Tools

Collection of 9 specialized HVAC calculation and diagnostic tools designed for field technicians and contractors. These tools help with critical HVAC service tasks including airflow analysis, refrigerant calculations, system diagnostics, and component sizing.

Base URL

https://test.hub.bluontoolbox.com/uat

Available Tools

1. Airflow Calculator

Estimate system airflow from temperature readings

2. Airflow Diagnostic

Diagnose airflow/load issues with recommendations

3. Calculate Subcool

Calculate subcooling from pressure and temperature

4. Calculate Superheat

Calculate superheat from pressure and temperature

5. Ductulator

Calculate duct sizes for airflow requirements

6. Nitrogen Pressure Test

Analyze pressure changes during leak testing

7. Pressure Set Points

Get reference pressure targets for system balance

8. Target Superheat

Calculate target superheat for fixed orifice systems

9. TXV Size Calculator

Evaluate TXV sizing for proper system operation

1. Airflow Calculator

Provides quick estimation of system airflow based on wet bulb temperature readings.

Endpoint

POST /gateway/{partner}/tools/airflow-calculator

Parameters

  • return_air (number, required) - Return air wet bulb temperature (°F)
  • supply_air (number, required) - Supply air wet bulb temperature (°F)
  • nominal_tons (number, required) - System nominal tonnage

Response

Returns estimated_cfm - Standard is 400 CFM per ton. Compare to nominal (tonnage × 400) to assess airflow.

2. Airflow Diagnostic

Diagnoses high/low airflow/load issues with detailed analysis and recommendations.

Endpoint

POST /gateway/{partner}/tools/airflow-diagnostic

Same parameters as Airflow Calculator. Returns diagnostic status (red/yellow/green) and percentage vs nominal CFM.

3. Calculate Subcool

Calculates subcooling value based on refrigerant type, pressure, and temperature readings.

Endpoint

POST /gateway/{partner}/tools/calculate-sub-cool

Parameters

  • gas_type (string, required) - Refrigerant type (see supported types below)
  • pressure (number, optional) - Liquid line pressure (PSIG)
  • temperature (number, optional) - Liquid line temperature (°F)

Response

  • bubble_temp - Saturation temperature for condensation
  • sub_cool - Temperature difference (Target: 8-12°F for R-410A)

4. Calculate Superheat

Calculates superheat value based on refrigerant type, pressure, and temperature readings.

Endpoint

POST /gateway/{partner}/tools/calculate-super-heat

Parameters

  • gas_type (string, required) - Refrigerant type
  • pressure (number, optional) - Suction line pressure (PSIG)
  • temperature (number, optional) - Suction line temperature (°F)

Response

Returns dew_temp and super_heat. Target: 5-15°F for TXV systems, 10-20°F for fixed orifice.

5. Ductulator

Calculates round and rectangular duct sizes based on airflow requirements.

Endpoint

POST /gateway/{partner}/tools/ductulator

Parameters

  • airflow_rate (number, required) - Required airflow (CFM)
  • maximum_air_velocity (number, required) - Maximum velocity (FPM)
  • maximal_static_loss (number, required) - Maximum static pressure loss

Response

Returns round_sizes and rectangular_sizes with dimensions, FPM, and pressure loss.

6. Nitrogen Pressure Test

Calculates expected pressure changes during nitrogen pressure testing based on temperature variations.

Endpoint

POST /gateway/{partner}/tools/nitrogen-pressure-test

Parameters

  • initial_pressure & initial_temperature (required)
  • final_pressure & final_temperature (required)

Purpose

Returns expected pressure using Gay-Lussac's Law. Difference between expected and actual indicates leaks.

7. Pressure Set Points

Provides reference pressure targets to maintain optimal temperatures across system components.

Endpoint

POST /gateway/{partner}/tools/pressure-set-points

Parameters

  • liquid_line (number, required) - Liquid line pressure
  • discharge_line (number, required) - Discharge line pressure
  • suction_line (number, required) - Suction line pressure

Purpose

Returns adjusted pressures for optimal condensing, compression ratio, and evaporator operation.

8. Target Superheat

Calculates target superheat based on outdoor and indoor conditions for fixed orifice systems.

Endpoint

POST /gateway/{partner}/tools/target-super-heat

Parameters

  • outdoor_air_temp (number, required) - Outdoor dry bulb (°F)
  • return_air_temp_wetbulb OR return_air_temp_drybulb + return_air_humidity

Response

Returns target_sh and safe_rage for proper compressor protection.

9. TXV Size Calculator

Evaluates whether a TXV (Thermostatic Expansion Valve) is properly sized for the system.

Endpoint

POST /gateway/{partner}/tools/txv-size

Parameters

  • tonnage (number, required) - Total nominal tonnage per circuit
  • minimum_capacity (number, required) - Smallest compressor stage per circuit

Purpose

Evaluates turndown ratio (2:1 to 2.5:1 max). Oversized TXVs cause floodback. Recommends EEV for better turndown (up to 10:1).

Supported Refrigerants

The following refrigerant types are supported across refrigerant calculation tools:

R-22R-134AR-404AR-407CR-410AR-421AR-422BR-422DR-427AR-438AR-458AR-507