Comparison

HVAC Tools PT Chart vs HydroCalc

Price, ratings, monetisation and update history for both apps, side by side โ€” with what reviewers say about each.

Head to head
About

HVAC Tools PT Chart

Features
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Gauge is a field toolkit for HVAC and refrigeration technicians: a pressure-temperature chart for 10 refrigerants, superheat and subcooling calculators, troubleshooting checklists and a service call log with PDF reports. PT CHART - R-410A and R-22 free; R-134a, R-407C, R-404A, R-32, R-454B, R-290, R-438A and R-422D with Pro - Look up the saturation temperature for a pressure, or the pressure for a temperature - Scroll the full table from -40ยฐF, with safety notes for the A2L (R-32, R-454B) and A3 (R-290) refrigerants CALCULATORS - Superheat: suction pressure and suction line temperature give the saturation temperature and the superheat - Subcooling: liquid line pressure and liquid line temperature - Temperature split: return and supply air - Ohm's Law: enter any two of volts, amps, ohms and watts - Pro: airflow (required CFM from BTU/h or tons and the temperature split), duct sizing (round and rectangular sizes from CFM and air velocity), capacitor check (measured against rated ยตF) and voltage drop (copper wire by AWG, one-way length, amps and supply voltage) Superheat, subcooling, temperature split, capacitor and voltage drop results are color-coded against typical ranges, with what to check next. SERVICE CALL LOG - Customer or address, complaint, system type, make and model - Suction and liquid pressure, superheat, subcooling, suction line, liquid line, supply and return air temperatures, compressor amps - Your diagnosis, the work performed, refrigerant type and amount, parts, notes, cost and time on the job - Free: up to 10 service calls. Pro: unlimited calls, search, and a PDF service report with your name and certification that you can share with the customer REFERENCE - Step-by-step checklists: AC not cooling (free), furnace not heating and heat pump not heating (Pro) - Typical ranges for superheat, subcooling, temperature split and compressor amps - Refrigerant facts: GWP, A2L or A3 safety class and phase-down status - System types, a copper wire ampacity table and an EPA 608 overview (certification types and key rules) AI ADVISOR (PRO) Describe a symptom or a set of readings and get a short written answer from an AI model. It sends only the message you type and needs an internet connection. AI answers can be wrong: check them against your own readings and the equipment manufacturer's data. GOOD TO KNOW - Gauge works in US units: ยฐF, psig, CFM, inches, feet, AWG and pounds - The PT chart, calculators, reference and service log work without a connection GAUGE PRO Free: the PT chart for R-410A and R-22, the superheat, subcooling, temperature split and Ohm's Law calculators, up to 10 service calls, the AC checklist and the reference tables. Pro adds the other 8 refrigerants, the airflow, duct sizing, capacitor and voltage drop calculators, unlimited service calls with search and PDF reports, the furnace and heat pump checklists and the AI Advisor. In the US, Gauge Pro is $4.99 a month or $39.99 a year (US prices; other countries see their own price in the app). Subscriptions renew automatically unless cancelled at least 24 hours before the end of the period. Manage them in your App Store account settings. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

About

HydroCalc

Features
Read full description

HydroCalc is a calculation aid for heating and HVAC technicians. Calculate flow from heat output and temperature difference alongside the existing hydraulic calculators. CIRCUIT PROJECTS Create named projects and group circuits by room, category or floor. Record heat output, temperature difference and input sources for each circuit. View total heat output and required flow together. BASELINE AND COMPARISON Capture a fixed baseline and edit later proposals independently. Review differences in totals and share a calculation worksheet with inputs, sources and comparison. German and English. Local projects and calculations work offline. Existing purchase unlocks remain available. Professional calculation aid: manufacturer data, applicable rules, system design and actual measurements take precedence. Check results against the real installation. EULA: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ COMMISSIONING VISITS Record measured flow for each circuit and compare it with the design targets frozen when the visit is saved. An adjustable project tolerance makes deviations clear. Earlier visits remain unchanged after later design edits. Calculated targets and measured values stay separate.

Screenshots

HVAC Tools PT Chart4 screens

Verdict

The call

HVAC Tools PT Chart and HydroCalc are too close to call on the numbers: across 6 compared parameters โ€” price, update cadence, ads and in-app purchases among them โ€” neither pulls far enough ahead to decide it. What separates them is feature set and interface, not measurable difference.

Scored on Price ยท Rating ยท Positive reviews ยท Number of ratings ยท Update frequency ยท Ads ยท In-app purchases ยท Monetization ยท Best chart rank ยท Devices ยท Requires iOS

CostPrice ยท In-app purchases ยท Ads ยท Monetization

Both are free to download. HVAC Tools PT Chart sells 3 in-app purchases, starting at $4.99 per month and HydroCalc sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

HVAC Tools PT Chart ships an update monthly, HydroCalc every 5 weeks. The most recent releases landed on November 9, 2026 and November 6, 2026 respectively.

ScorecardNo meaningful differences
HVAC Tools PT Chart versus HydroCalc: the parameters behind the verdict, then further details
ParameterHVAC Tools PT ChartHydroCalc
PriceFreeFree
Update frequencyMonthly โ€” betterEvery 5 weeks
AdsNoNo
In-app purchasesYesYes
DevicesiPhoneiPhone, iPad โ€” better
Requires iOS1817.0 โ€” better
Further details โ€” not scored
Size9 MB2 MB
Age rating4+4+
DeveloperKarol JaworskiPiotr Kaminski

In-app purchases

3 purchases

HVAC Tools PT Chart

Subscriptions3
  • Gauge Pro$4.991 Month
  • Gauge Pro1 Year trial$39.991 Year
  • Gauge Pro$39.991 Year
1 purchases

HydroCalc

One-time1
  • HydroCalc Pro$3.99

Questions

Is HVAC Tools PT Chart free?
HVAC Tools PT Chart is free to download, with in-app purchases available.
Is HydroCalc free?
HydroCalc is free to download, with in-app purchases available.
Do HVAC Tools PT Chart or HydroCalc have ads?
Neither HVAC Tools PT Chart nor HydroCalc shows ads.
Which is updated more often, HVAC Tools PT Chart or HydroCalc?
HVAC Tools PT Chart ships an update monthly, and HydroCalc every 5 weeks. Most recently, HVAC Tools PT Chart was updated on November 9, 2026 and HydroCalc on November 6, 2026.

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