Comparison

Parallel vs HVAC Tools PT Chart

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

Head to head
About

Parallel

Features
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Parallel makes it easy to align objects for construction and architectural purposes. Pair two devices and have Parallel indicate when your devices' edges have a parallel or perpendicular relationship. Parallel is especially useful for precision construction of things like gardening squares, tree houses, or anything involving the distant alignment of objects! โ€“ Developed by Omar Al-Ejel, Class of 2017

About

HVAC Tools PT Chart

Features
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Gauge is the field reference app built for HVAC and refrigeration technicians. Every diagnostic tool you reach for on the job - pressure-temperature charts, superheat and subcooling calculators, airflow, duct sizing, Ohm's Law, capacitor check, voltage drop, and AI-powered diagnostics - in one fast, glove-friendly interface. Offline. Built for the field. -- 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. Free tier includes R-410A and R-22. -- 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. -- AI HVAC ADVISOR (Pro) -- Describe your symptoms - high head pressure, low suction, ice on the coil, unit not cooling - and get expert diagnostic guidance from AI. Responses are concise, field-applicable, and reference specific pressures and temperatures. Not a generic chatbot. A diagnostic partner built for HVAC technicians. -- SERVICE CALL LOG -- Log every job. Refrigerant type, system make and model, complaint, pressures, temperatures, amp readings, diagnosis, parts, notes. Full 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 interface readable in direct sunlight. Monospaced numbers so PT chart columns align perfectly. All calculators work offline. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

Parallel4 screens
HVAC Tools PT Chart4 screens

Verdict

The call

The clearest difference is in-app purchases: Parallel at none against HVAC Tools PT Chart's 3. Parallel also leads on iOS requirement (8.0 vs 18). On price, ads and device support there is nothing between them.

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. Parallel asks for nothing beyond the download.

Scorecard2 real differences ยท 4 level
Parallel versus HVAC Tools PT Chart: the parameters behind the verdict, then further details
ParameterParallelHVAC Tools PT Chart
PriceFreeFree
Update frequencyโ€”Every 5 months
AdsNoNo
In-app purchasesNo โ€” betterYes
DevicesiPhone, iPod โ€” betteriPhone
Requires iOS8.0 โ€” better18
Further details โ€” not scored
Size10 MB9 MB
Age rating4+4+
DeveloperOmar Al-EjelKarol Jaworski

In-app purchases

None

Parallel

No 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

Questions

Is Parallel free?
Parallel is free to download, with no in-app purchases.
Is HVAC Tools PT Chart free?
HVAC Tools PT Chart is free to download, with in-app purchases available.
Do Parallel or HVAC Tools PT Chart have ads?
Neither Parallel nor HVAC Tools PT Chart shows ads.

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