HVAC Tools PT Chart - Gauge

Gauge is the field reference app built for HVAC and refrigeration technicians. Every diagnostic tool you reach for on the job - pressure-temperature charts, superheat and subcooling calculators, airflow, duct sizing, Ohm's Law, capacitor check, voltage drop, and AI-powered diagnostics - in one fast, glove-friendly interface. Offline. Built for the field.

-- PRESSURE-TEMPERATURE CHART --

Full PT chart for R-410A, R-22, R-134a, R-407C, R-404A, R-32, R-454B, R-290, R-438A, R-422D and more. Enter a pressure or temperature and the matching value highlights instantly. Free tier includes R-410A and R-22.

-- CALCULATORS --

Superheat Calculator
Enter suction pressure and suction line temperature. Gauge looks up saturation temperature from the PT chart and calculates actual superheat instantly.

Subcooling Calculator
Enter liquid line pressure and liquid line temperature for accurate subcooling on any common refrigerant.

Temperature Split Calculator
Supply and return air temps. Actual vs target split shown side by side.

Airflow / CFM Calculator (Pro)
Duct dimensions and velocity to CFM conversion. Essential for commissioning and balancing.

Duct Sizing Calculator (Pro)
Diameter and velocity from CFM and friction rate. Design or diagnose duct systems fast.

Ohm's Law Calculator
Solve for voltage, current, resistance, or power. Enter any two values.

Capacitor Check Calculator (Pro)
Rated vs measured microfarads with pass/fail result and tolerance band.

Voltage Drop Calculator (Pro)
Wire length, gauge, load current, and system voltage to determine voltage drop percentage.

-- AI HVAC ADVISOR (Pro) --

Describe your symptoms - high head pressure, low suction, ice on the coil, unit not cooling - and get expert diagnostic guidance from AI. Responses are concise, field-applicable, and reference specific pressures and temperatures. Not a generic chatbot. A diagnostic partner built for HVAC technicians.

-- SERVICE CALL LOG --

Log every job. Refrigerant type, system make and model, complaint, pressures, temperatures, amp readings, diagnosis, parts, notes. Full history searchable by date or system. Free tier includes up to 10 service calls.

-- REFERENCE LIBRARY --

Troubleshooting guides for AC systems, gas furnaces, and heat pumps - step-by-step diagnostic checks organized by symptom. Refrigerant quick-reference with GWP, flammability rating, and phase-down status. System type overviews. Copper wire ampacity table. EPA 608 certification reference.

-- DESIGNED FOR THE FIELD --

Large tap targets for gloved hands. High-contrast interface readable in direct sunlight. Monospaced numbers so PT chart columns align perfectly. All calculators work offline.

Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/