Refrigerant Charge Calculator

Refrigerant Charge Calculator — built for working HVAC and refrigeration techs. Open it at the condenser, pick the refrigerant, type your superheat or subcooling, and get a clear field verdict: Add, Hold, or Remove. No classroom theory. No 20-step wizards. Just the number you need, in the unit you work in.

WHAT YOU CAN DO

• Charge check by superheat — fixed-orifice, piston, or cap tube systems, with target ranges interpolated from indoor wet-bulb and outdoor dry-bulb

• Charge check by subcooling — TXV and EEV systems, measured against the nameplate target

• Line-set charge estimation — add-a-length and long-line corrections done in seconds

• Pressure–Temperature reference — 1-psig precision, with bubble, dew, and mid-point readings for zeotropic blends (glide shown explicitly)

• Altitude-corrected pressures — auto-detected from your location, or set the elevation by hand

• Saved jobs — address and GPS coordinates tagged from the map

• One-tap PDF job sheets — header, readings, verdict, notes — ready to email to the building owner, property manager, or warranty adjuster

• Unit toggles everywhere — °F / °C, psig / bar, imperial / metric line sets

• Fully offline — attics, basements, rooftop curbs, mechanical rooms with no signal

REFRIGERANTS COVERED — 86 TOTAL

A2L low-GWP (2025 compliant)
R-32 · R-454A · R-454B · R-454C · R-452B · R-457A · R-1234yf · R-1234ze(E) · R-1234ze(Z) · R-1243zf · R-1336mzz(E)

HFC workhorses
R-410A · R-410B · R-134a · R-404A · R-407A · R-407C · R-407F · R-448A · R-449A · R-449B · R-452A · R-507A · R-513A · R-515B

Legacy and service blends
R-22 · R-11 · R-12 · R-123 · R-124 · R-125 · R-500 · R-502 · R-417A · R-421A · R-422A · R-422B · R-422C · R-422D · R-427A · R-438A · R-453A

Naturals
R-290 propane · R-600a isobutane · R-717 ammonia · R-744 CO₂ · R-1270 propylene

Plus 30+ less-common 400-series blends you won't find on a pocket slider — full list browsable inside the app.

REFRIGERANT DETAIL PAGES

Every refrigerant comes with the data you actually look up on the job:
• GWP and ASHRAE safety class
• Tank color code
• Occupational Exposure Limit (OEL)
• Temperature glide for blends
• Critical point and molecular weight
• Common applications and replacement notes

WHO IT'S FOR

• Residential and light-commercial HVAC service techs
• Refrigeration techs working supermarket R-744 racks and R-290 cases
• A2L installers catching up on R-454B and R-32
• Apprentices studying for EPA 608 and ESCO certification
• Shop owners who want every tech reading the same charge verdict

WHY TECHS CHOOSE IT

• Offline-first — calculations run on device, no spinning loader in a crawlspace
• No account required — open the app, run the math, close the app
• Verdict first, numbers after — the screen tells you what to do before making you scroll
• Your jobs stay on your phone — nothing leaves the device without a tap from you
• Built by listening to techs, not classroom instructors

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