HVAC RefCharge vs Appion Central
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
HVAC RefCharge
This app helps HVAC technicians quickly calculate refrigerant superheat and subcool levels. It supports over 100 refrigerants and offers interactive adjustments for precise charging decisions. Features include atmospheric pressure adjustments and unit customization.
- Superheat and subcool calculations
- Supports 100+ refrigerants
- Interactive slider for adjustments
- Atmospheric pressure compensation
- Customizable input types
- Project photo assignment
- Email report generation
- English/Metric unit display
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The HVAC RefCharge app is a refrigerant charging calculator that allows HVAC technicians to perform superheat and subcool refrigerant charge calculations on-the-fly. This app includes pressure/temperature data for over 100 refrigerants. This is a universal app that works on both the iPhone and iPad. This app now includes the HVAC Equipment Locator. Click here for details: http://bit.ly/1yTq539 The following is a list of additional features: 1. Perform superheat refrigerant charge calculations for 100+ different refrigerants. Input the indoor wet-bulb and outdoor dry-bulb temps. to get the target superheat temperature. Then, specify the suction line temperature and pressure to get the actual superheat temperature. The difference tells you whether to charge or not. Also, the app auto-assigns the dew version of azeotropic refrigerant to superheat, if applicable. 2. Perform subcool refrigerant charge calculations for 100+ different refrigerants. Input the indoor wet-bulb and outdoor dry-bulb temps. to get the target subcool temperature. Then, specify the liquid line temperature and pressure to get the actual subcool temperature. The difference tells you whether to charge or not. Also, the app auto-assigns the bubble version of azeotropic refrigerant to subcool, if applicable. 3. Use an interactive slider control to increase or decrease all values and immediately observe calculated results. Also, the slider control allows for "incremental" changes so you can ever-so-slightly change values to observe newly calculated results. 4. Specify atmospheric pressure (other than standard 14.7 psi) so that calculated pressures are adjusted for high elevations like those in Denver and elsewhere. 5. Customize input types so that you can specify manufacturer-specified target superheat/subcool or input indoor dry-bulb/indoor relative humidity in place of indoor wet-bulb temperature. 6. Take a photo and assign it to the project 7. Send an email that includes all inputs, results, and the photo with a custom message 8. Display input and result values in either English or Metric units
Appion Central
Manage your HVAC tools and connect to the web portal. This app provides a mobile interface for your Appion products.
- Manage Appion products
- Interface with Appion Portal
- Mobile tool management
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Appion Central is designed to allow users to manage their Appion products as well as provide an interface with the Appion Portal web service.
Screenshots
Verdict
The clearest difference is price: Appion Central at Free against HVAC RefCharge's $9.99. Appion Central also leads on in-app purchases (none vs 1) and update cadence (every 5 weeks vs every 11 months). On review sentiment, ads and device support there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
Appion Central is free to download; HVAC RefCharge costs $9.99 up front. HVAC RefCharge sells 1 one-off in-app purchase. Appion Central asks for nothing beyond the download.
HVAC RefCharge ships an update every 11 months, Appion Central every 5 weeks. The most recent releases landed on September 21, 2026 and June 5, 2026 respectively.
| Parameter | HVAC RefCharge | Appion Central |
|---|---|---|
| Price | $9.99 | Free — better |
| Rating | — | 2.8 (14 ratings) — better |
| Positive reviews | 33.3% of reviews — better | 28.6% of reviews |
| Number of ratings | — | 14 — better |
| Update frequency | Every 11 months | Every 5 weeks — better |
| Ads | No | No |
| In-app purchases | Yes | No — better |
| Monetization | Paid | Free — better |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Requires iOS | 15.6 | 13.0 — better |
| Further details — not scored | ||
| Size | 22 MB | 35 MB |
| Age rating | 4+ | 4+ |
| Developer | Carmel Software Corporation | Appion Inc. |
Customer experience
HVAC RefCharge
Appion Central
In-app purchases
HVAC RefCharge
- HVAC Equipment Locator$9.99
Appion Central
No in-app purchases
