# HVAC Tools PT Chart - Gauge — Superheat, PT Chart & Service

> Superheat, PT Chart & Service (iPhone/iPad app by Karol Jaworski.)

- Source: https://appshunter.io/ios/app/hvac-tools-pt-chart-gauge/id6760602879 (this page in markdown: same URL + `.md`)
- Developer: [Karol Jaworski](https://appshunter.io/developer/1799974477)
- Category: Utilities, Productivity
- Price: Free with in-app purchases
- Age rating: 4+
- Requires: iOS 18 · 2 MB
- Languages: American English
- Released: 2026-04-02
- Data updated: 2026-06-21
- User reviews in markdown: https://appshunter.io/ios/app/hvac-tools-pt-chart-gauge/id6760602879/reviews.md

## What is HVAC Tools PT Chart?

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

-- 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.

-- 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 in the table. Free tier includes R-410A and R-22.

-- AI HVAC ADVISOR (Pro) --

Describe your symptoms - high head pressure, low suction, ice on the coil, unit running but not cooling - and get expert diagnostic guidance from Grok AI. Responses are concise, field-applicable, and reference specific pressures and temperatures. This is not a chatbot - it's a diagnostic partner.

-- SERVICE CALL LOG --

Log every job. Refrigerant type, system make and model, complaint, pressures, temperatures, amp readings, diagnosis, parts, notes. Full job 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 white interface readable in direct sunlight. Monospaced numbers so PT chart columns align perfectly. All calculators work offline - no internet required for PT charts, superheat, subcooling, or any local calculator.

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

## Pricing and in-app purchases

Base price: Free.

**Subscriptions**

| Subscription | Price | Period |
| --- | --- | --- |
| Gauge Pro | $39.99 | per year |
| Gauge Pro | $39.99 | per year |
| Gauge Pro | $4.99 | per month |



## Version history (last 1 release)

### 1.0 — 2026-04-02

No release notes.

## More apps by Karol Jaworski

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All apps by Karol Jaworski: https://appshunter.io/developer/1799974477

## Related topics

[pt chart refrigeration](https://appshunter.io/ios/topics/pt-chart-refrigeration)

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-06-21.*