# RadiatorOutput vs Heat Engineer

The clearest difference is in-app purchases: RadiatorOutput at none against Heat Engineer's 1. RadiatorOutput also leads on review sentiment (100% vs 79%) and device support (4 vs 2). Heat Engineer's advantage is update cadence (every 2 months vs every 8 months). On price, ads, monetization model and iOS requirement there is nothing between them.

Both are free to download. Heat Engineer sells 1 one-off in-app purchase. RadiatorOutput asks for nothing beyond the download.

RadiatorOutput ships an update every 8 months, Heat Engineer every 2 months. The most recent releases landed on September 26, 2026 and October 2, 2026 respectively.

## The numbers

| Metric | RadiatorOutput | Heat Engineer |
| --- | --- | --- |
| Price | Free | Free |
| Positive reviews | **100.0% of reviews** | 78.9% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 8 months | **Every 2 months** |
| Monetization | Free | Free |
| Size | 1 MB | 203 MB |
| Requires iOS | **15.0** | 16.4 |
| Devices | **iPhone, iPad, iPod, Mac** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Sebastjan Valic](https://appshunter.io/developer/503687385) | [Heat Engineer Software Ltd](https://appshunter.io/developer/1461678894) |

## What reviewers say

### RadiatorOutput

[App page](https://appshunter.io/ios/app/radiatoroutput/id503687382)

Calculate radiator heat output based on water and air temperatures. Ensure optimal energy efficiency and cost savings by selecting the correct radiator size for any heating system, including those with low water temperatures. Supports metric units and can also calculate cooling output for convectors and fan-coils.

**Highlights:** Calculate radiator heat output, Adjust for water and air temperatures, Optimize energy efficiency, Supports low water temperature systems, Calculate cooling output, Metric units only

**Features:** Vision Pro support

**In-app purchases:** none


### Heat Engineer

[App page](https://appshunter.io/ios/app/heat-engineer/id879510552)

This app assists heating engineers and surveyors in collecting property data for heating system installations. It supports heat loss reports for various technologies and includes tools for sound assessments and quick estimations. Data is automatically saved for later review and amendment.

**Highlights:** Heat loss survey for BS EN 12831, CIBSE, and MCS standards, MCS 020 sound assessment for Air Source Heat Pumps, Quick heat loss estimator tool, Automatic data saving and history for amendments, Room-by-room heat loss calculation, Photo capture for rooms and installation locations, Fuel comparisons and running cost calculations

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| MCS 020 PDF Report Token | $2.99 | one-time |


## Frequently asked questions

### Is RadiatorOutput free?

RadiatorOutput is free to download, with no in-app purchases.

### Is Heat Engineer free?

Heat Engineer is free to download, with in-app purchases available.

### Do RadiatorOutput or Heat Engineer have ads?

Neither RadiatorOutput nor Heat Engineer shows ads.

### Which is updated more often, RadiatorOutput or Heat Engineer?

RadiatorOutput ships an update every 8 months, and Heat Engineer every 2 months. Most recently, RadiatorOutput was updated on September 26, 2026 and Heat Engineer on October 2, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*