# TLDR Review: A.O. Smith 40-gallon Water Heater

*Published: 2026-03-02 | Updated: 2026-03-02 | Source: https://shopsavvy.com/reviews-tldr/a.o.-smith-40-gallon-water-heater*

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## Product: A.O. Smith ProMax Plus 40 Gallon
**Brand:** AO Smith

## Pros
- Heats water almost immediately on demand
- Runs for brief periods only when hot water is drawn, improving efficiency
- Notable improvement over older heating systems
- Provides good value
- Outstanding quality compared to other units

## Bottom Line

Based on reviews we've collected, this A.O. Smith propane water heater gets high marks for responsive heating and efficiency. Reviewers consistently praise its reliability and feel they're getting solid value at $753.29, especially compared to older systems. Just make sure you have a propane supply lined up, because this unit is designed to run on that fuel source—but if you do, you've got yourself a dependable hot water solution.

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*About this review: We pulled together findings from professional and user reviews, and cross-referenced them with ShopSavvy's pricing data from thousands of retailers to give you the short version.*