# Superheat & Subcool Calc — 10 Refrigerants Diagnostics > HVAC diagnostic tool for superheat, subcooling, and refrigerant charge calculations. (iPhone/iPad app by Rizvan Adzhoian.) - Source: https://appshunter.io/ios/app/superheat-and-subcool-calc/id6764646450 (this page in markdown: same URL + `.md`) - Developer: [Rizvan Adzhoian](https://appshunter.io/developer/1891746079) - Category: Utilities, Business - Price: $0.99 with in-app purchases - Rating: 1.00/5 from 1 App Store ratings - Age rating: 17+ - Requires: iOS 13.0 · 34 MB - Languages: American English - Released: 2026-05-04 - Data updated: 2026-08-25 - Monetization: paid - User reviews in markdown: https://appshunter.io/ios/app/superheat-and-subcool-calc/id6764646450/reviews.md ## What is Superheat & Subcool Calc? HVAC Superheat & Subcool Calculator is the professional field diagnostic tool for AC service and system commissioning. Calculate superheat, subcooling, and saturation for 10 refrigerants including R-410A, R-454B (EPA 608 transition), and R-32 with smart charge diagnostics and color-coded results for instant field diagnostics. FEATURES: Instant Superheat & Subcooling Calculation - Get results in seconds Smart Charge Diagnostics - Normal, Low, or High with recommendations 10 Refrigerants Supported - R-410A, R-22, R-454B, R-32, R-407C, R-134a, R-404A, R-507A, R-290, R-717 Metering Device Support - TXV (expansion valve) or fixed orifice Color-Coded Results - Green/yellow/red for quick decisions P-T Saturation Data - NIST REFPROP-grade, verified against manufacturer charts Zeotropic Blend Support - Correct bubble/dew handling for blends 100% OFFLINE: All refrigerant data built-in. Works on job sites without cellular coverage. HOW IT WORKS: 1. Select refrigerant (R-410A, R-454B, R-32, etc.) 2. Select metering device (TXV or fixed orifice) 3. Enter suction pressure & temperature 4. Enter liquid pressure & temperature 5. Get instant superheat, subcooling & charge diagnosis UNDERSTANDING RESULTS: Superheat - Temperature rise above saturation on low side. Normal 10-20°F TXV, 15-25°F fixed orifice. Low indicates overcharge; high indicates undercharge or low airflow. Subcooling - Temperature drop below saturation on high side. Normal 10-20°F. Low indicates undercharge; high indicates overcharge. DIAGNOSTICS: Green - Normal charge, optimal operation Yellow - Borderline condition requiring attention Red - Undercharge, overcharge, or airflow issue SUPPORTED REFRIGERANTS: R-410A (residential), R-22 (legacy), R-454B (EPA replacement), R-32 (mini-splits), R-407C (commercial), R-134a (auto AC), R-404A (refrigeration), R-507A (low-temp), R-290 (propane), R-717 (ammonia) OPTIONAL PRO UPGRADE — $2.99 ONE-TIME IN-APP PURCHASE The following features require a separate one-time in-app purchase. They are not required to use the calculator: • Unlimited saved calculation history • PDF export of results • Dark theme • Ad-free experience USE CASES: AC service calls, refrigerant charge diagnostics, equipment commissioning, troubleshooting complaints, EPA 608 certification study, preventive maintenance checks, system optimization, R-454B transition preparation. PERFECT FOR: HVAC technicians, refrigeration mechanics, AC contractors, HVAC apprentices, building engineers, commissioning specialists, HVAC students. All P-T saturation data from NIST REFPROP-grade equations of state, cross-checked against manufacturer charts, covering -60°F to +150°F, with correct bubble/dew blend calculations. Part of HVACTools Suite - professional HVAC technician tools for field service and diagnostics. ## Key features - Instant Superheat & Subcooling Calculation - Smart Charge Diagnostics - 10 Refrigerants Supported - Metering Device Support - Color-Coded Results - P-T Saturation Data - Offline Functionality ## Pricing and in-app purchases Base price: $0.99. **One-time purchases** | Purchase | Price | Type | | --- | --- | --- | | Pro Unlock | $2.99 | one-time | ## Frequently asked questions about Superheat & Subcool Calc ### What is Superheat & Subcool Calc used for? Superheat & Subcool Calc is a professional field diagnostic tool for HVAC service and system commissioning. It calculates superheat, subcooling, and saturation for various refrigerants, providing smart charge diagnostics and color-coded results for instant field decisions. ### How does Superheat & Subcool Calc work? Users select the refrigerant and metering device, then enter suction and liquid pressures and temperatures. The app then provides instant superheat, subcooling, and charge diagnosis results. ### Does Superheat & Subcool Calc support new refrigerants like R-454B? Yes, Superheat & Subcool Calc supports 10 refrigerants, including R-410A, R-454B (EPA 608 transition), and R-32, along with legacy and other common refrigerants. ### Can I use Superheat & Subcool Calc without an internet connection? Yes, the app is 100% offline. All refrigerant data is built-in, allowing it to work on job sites without cellular coverage. ### What are the normal ranges for superheat and subcooling? Normal superheat is typically 10-20°F for TXV and 15-25°F for fixed orifice. Normal subcooling is generally 10-20°F. The app provides context for low or high readings. ### What is the price of Superheat & Subcool Calc? Superheat & Subcool Calc is available for a one-time purchase of $0.99. ### Does Superheat & Subcool Calc have ads? The base version of Superheat & Subcool Calc does not contain advertisements. An optional pro upgrade offers an ad-free experience along with other features. ### What features are included in the optional Pro Upgrade? The optional Pro Upgrade, available for a one-time in-app purchase of $2.99, includes unlimited saved calculation history, PDF export of results, a dark theme, and an ad-free experience. ## Version history (last 3 releases) ### 1.0.8 — 2026-06-11 What's new: - Recalculated all refrigerant P-T saturation tables to NIST REFPROP-grade accuracy, verified against manufacturer charts - Extended pressure range to -60...+150 F saturation for hot condenser readings - Corrected temperature glide values for R-454B, R-407C and R-404A ### 1.0.7 — 2026-05-18 What's new: - Updated metadata for clarity per App Store guidelines - Optional Pro upgrade is a separate one-time in-app purchase (not required for calculator features) ### 1.0.5 — 2026-05-04 No release notes. ## Apps similar to Superheat & Subcool Calc | App | Rating | Price | Category | | --- | --- | --- | --- | | [HVAC Tools PT Chart - Gauge](https://appshunter.io/ios/app/hvac-tools-pt-chart-gauge/id6760602879) | — | Free | Utilities | | [HVAC Load & Refrigerant Calc](https://appshunter.io/ios/app/hvac-load-and-refrigerant-calc/id6762048483) | — | Free | Utilities | | [Flux HVAC: Tech Calculator](https://appshunter.io/ios/app/flux-hvac-tech-calculator/id6756405485) | 5.0 (1) | Free | Utilities | | [UEi DTHA2](https://appshunter.io/ios/app/uei-dtha2/id1452986649) | 4.0 (4) | Free | Utilities | | [Refrigerant Charge Calculator](https://appshunter.io/ios/app/refrigerant-charge-calculator/id6762469018) | 4.4 (10) | Free | Utilities | | [HYmpulsion](https://appshunter.io/ios/app/hympulsion/id1527452664) | — | Free | Utilities | ## More apps by Rizvan Adzhoian - [Conduit Fill Calculator-NEC](https://appshunter.io/ios/app/conduit-fill-calculator-nec/id6761846849) - [Electrical Load Calc NEC](https://appshunter.io/ios/app/electrical-load-calc-nec/id6763250945) - [Transformer Calc NEC](https://appshunter.io/ios/app/transformer-calc-nec/id6763311943) - [Voltage Drop Calc NEC](https://appshunter.io/ios/app/voltage-drop-calc-nec/id6763312448) - [Grounding Size Calc NEC](https://appshunter.io/ios/app/grounding-size-calc-nec/id6763312724) - [Breaker Size Calc NEC](https://appshunter.io/ios/app/breaker-size-calc-nec/id6763312865) All apps by Rizvan Adzhoian: https://appshunter.io/developer/1891746079 --- *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 2026-08-25.*