Airkit: HVAC Calculator
Charging, ductulator, PT chart
Only for iPhone
Free · In‑App Purchases · Designed for iPhone. Not verified for macOS.
iPhone
Superheat, target charge, the ductulator, PT charts, static pressure and MCA — every calculation a working tech needs. Fast, offline, A2L-ready.
Airkit is the all-in-one HVAC calculator built for working technicians. Superheat and subcooling, refrigerant charging, the ductulator, PT charts, airflow, static pressure, and the electrical numbers — every calc you reach for on a service call, in one fast, offline app.
Built for modern systems. Airkit handles A2L refrigerants (R-454B, R-32, R-454C) with glide done right — dew point for superheat, bubble point for subcooling — alongside R-410A, R-22, R-134a and 15+ more.
CHARGING
• Superheat & subcooling with live verdicts against your target
• Target superheat from indoor wet bulb + outdoor dry bulb (fixed orifice / piston)
• Delta T health check
• Charging assistant — pass, add, or recover refrigerant
REFRIGERANT
• PT chart — a pressure-temperature slider for 20+ refrigerants
• Line set charge — ounces per foot for the actual run
• A2L handling, oil pairing, and cylinder-color reference
AIRFLOW
• Ductulator — round & rectangular duct sizing by friction rate or velocity
• CFM per ton and target airflow
• Static pressure designer — TESP, filter and coil drops, friction rate
ELECTRICAL
• MCA / MOCP with copper wire sizing (NEC 2023)
• Capacitor check — rated vs. measured, plus under-load microfarads
• Ohm's Law and AC power
PLUS
• Unit converter — pressure, vacuum microns, temperature, airflow, capacity, length and more
• Offline reference: thermostat wiring, superheat/subcooling targets, duct velocity, line sets, ACR copper tube, refrigerant & oil pairing
WHY AIRKIT
• Works fully offline — no signal in the mechanical room, no problem
• No account, no sign-up
• Fast, glove-friendly, and readable in the dark or in glare
• Values consistent with NEC 2023 and ASTM B280 — always verify against the locally adopted code
• Available in 22 languages
Free to use, with an optional Pro unlock for the complete refrigerant set and advanced tools.
Airkit is an informational aid for trained HVAC/R professionals. Always follow equipment nameplates, OEM literature, and local code.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
Now in metric — and it still shows its work.
• Every tool works in metric: L/s or m³/h, mm, m/s, Pa, Pa/m, kW and grams. Round duct snaps to the EN 1506 series rather than to a converted inch.
• The reference library converts too. Velocity ranges, subcooling targets, charge limits and the copper tube table now read in your units instead of Fahrenheit and feet.
• A new install picks its units from your region, so there is nothing to set up first.
• Tap the bookmark on any tool to save what's on screen. It comes back under Saved with every field exactly as you left it.
• Every result has "Show calculation": the pressures, table look-ups and steps behind the number, written in your own units.
• Ohm's law fills in the third value for you, so volts, amps and ohms always agree.
• The PT chart tells you when a reading is off the refrigerant's table instead of answering anyway.
The developer, Chirag Arora, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Linked to You
The following data may be collected but it is not linked to your identity:
- Contact Info
- Identifiers
- Usage Data
- Diagnostics
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Chirag Arora
- Size
- 48.4 MB
- Category
- Utilities
- Compatibility
Requires iOS 15.0 or later.
- iPhone
Requires iOS 15.0 or later. - iPod touch
Requires iOS 15.0 or later. - Mac
Requires macOS 12.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
- English
- Age Rating
4+
- 4+
- In-App Purchases
Yes
- Airkit Pro - Yearly $9.99
- Airkit Pro - Monthly $2.99
- Copyright
- © 2026 Chiaro Apps
