# Plumbing Formulator vs Heat Engineer

The clearest difference is review sentiment: Heat Engineer at 79% against Plumbing Formulator's 9%. Heat Engineer also leads on iOS requirement (15.6 vs 18.6). On price, update cadence, ads and in-app purchases there is nothing between them.

Both are free to download. Plumbing Formulator sells 4 one-off in-app purchases and Heat Engineer sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

Both ship on a similar rhythm, roughly every 2 months. The most recent releases landed on August 23, 2026 and August 5, 2026 respectively.

## The numbers

| Metric | Plumbing Formulator | Heat Engineer |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.6 (7 ratings)](https://appshunter.io/ios/app/plumbing-formulator/id303497783/reviews)** | — |
| Number of ratings | **7** | — |
| Positive reviews | 9.1% of reviews | **78.9% of reviews** |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Every 2 months | Every 2 months |
| Monetization | Free | Free |
| Size | 123 MB | 44 MB |
| Requires iOS | 18.6 | **15.6** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Historycentral.com](https://appshunter.io/developer/1744330560) | [Heat Engineer Software Ltd](https://appshunter.io/developer/1461678894) |

## What reviewers say

### Plumbing Formulator

[App page](https://appshunter.io/ios/app/plumbing-formulator/id303497783)

This professional calculator app provides over 200 formulas, calculators, and reference materials for plumbers, HVAC technicians, and mechanical contractors. It covers a wide range of calculations for water flow, piping, drainage, water heaters, pumps, and more, all in one pocket-sized tool.

**Highlights:** Over 200 formulas and calculators, Water flow and supply calculations, Pipe and piping calculations, Drainage and venting calculations, Water heater and pump calculations, Reference charts and code books, Pipe cut list optimizer

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

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Pro Version | $1.99 | one-time |
| Pro Purchase | $3.99 | one-time |
| Starter | $5.99 | one-time |
| Growth | $9.99 | one-time |


### 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 Plumbing Formulator free?

Plumbing Formulator is free to download, with in-app purchases available.

### Is Heat Engineer free?

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

### Do Plumbing Formulator or Heat Engineer have ads?

Neither Plumbing Formulator nor Heat Engineer shows ads.

### Which is updated more often, Plumbing Formulator or Heat Engineer?

Plumbing Formulator ships an update every 2 months, and Heat Engineer every 2 months. Most recently, Plumbing Formulator was updated on August 23, 2026 and Heat Engineer on August 5, 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.*