Every propane heater gets a score from 0 to 100% built from six factors, which maps onto the 5-point rating shown on the site (a 0% score would be 1.5 stars; a perfect score, 5). Each factor is scored against fixed reference points, not against the other products in the list, so adding a new model never moves another model’s rating. Heaters are grouped by type, portable, tank top or forced air, and each group has its own price scale.
| Factor | Measures | Weight |
|---|---|---|
| Value | price per 1,000 BTU of heat | 25% |
| Safety | safety listing, low-oxygen, tip-over and flame-out shutoffs | 30% |
| Warranty | warranty length | 15% |
| Turndown | how low it can run, to stretch fuel and avoid overheating | 15% |
| Ignition | push-button or electric start | 10% |
| Fuel options | runs on 1 lb cylinders and a bulk tank | 5% |
Where the numbers come from
Heat output, safety features, safety listing, ignition, fuel options and warranty come from the maker’s product page, manual or warranty page, or the maker’s own copy on its Amazon listing. Heat output, noise and run time measured by independent testers are shown on product pages where they’ve been published.
Why heat output isn’t scored on its own
A bigger heater isn’t a better one: a 125,000 BTU torpedo heater would be dangerous in a tent, and a 3,800 BTU Little Buddy can’t warm a garage. Output goes into value instead, as price per 1,000 BTU, and how low a heater can turn down is scored separately.
The factors
Value is the current price divided by the heater’s highest output in thousands of BTU, on a log scale for each group, so going from $10 to $5 per 1,000 BTU counts as much as going from $20 to $10.
| Group | Scores 0 | Full marks |
|---|---|---|
| Portable | $20 per 1,000 BTU | $5 per 1,000 BTU |
| Tank top | $6 per 1,000 BTU | $1.50 per 1,000 BTU |
| Forced air | $5 per 1,000 BTU | $1 per 1,000 BTU |
Safety adds up four things:
| Feature | Share of the factor |
|---|---|
| A safety listing from a recognized lab (CSA, ETL, UL) | 40% |
| Shuts off if the oxygen in the air runs low | 20% |
| Shuts off if knocked over | 20% |
| Shuts the gas off if the flame goes out | 20% |
A listing means a lab has tested the heater to the standard for its type, such as ANSI Z21.11.3 for portable heaters or ANSI Z83.7 for construction heaters. A heater whose maker publishes no listing gets no credit for it. A shutoff the maker doesn’t state either way gets half credit.
Warranty: 1 year scores zero and 3 years full marks.
Turndown is the lowest setting as a share of the highest. A heater that turns down to a third of its full output stretches a tank three times as far once the space is warm, and is less likely to overheat a small space: one setting scores zero and 30% of full output scores full marks.
Ignition is full marks for push-button piezo or electric ignition and zero for a heater you light with a match or lighter.
Fuel options is full marks for a heater that runs on 1 lb cylinders and a bulk tank, and half marks for one that runs on only one of them.
What isn’t scored
Where the maker allows it to be used, coverage claims, noise, size, weight and looks are listed but not scored. Use matters most of all, so it’s shown at the top of every product page; pick the type first, then the heater. Independent tests are listed where they exist, but there are too few to score.
Missing data
If a figure isn’t published, that factor gets the neutral middle score (50) and the product page marks it as estimated. The safety listing is the exception: a listing has to be stated to count.
Ties and discontinued models
Products are ranked by score within each group. Discontinued models stay listed but rank below every current model and can be hidden with the “Hide discontinued” filter.