The Mr. Heater 20K Blue Flame Dual Fuel and the Mr. Heater 20K Radiant Dual Fuel are evenly matched, rated 4.2 and 4.2. The Mr. Heater 20K Blue Flame Dual Fuel costs $9.01 less ($199.99 vs $209).
A thermostat blue flame heater for a living room or cabin of up to about 700 sq ft that may switch between propane and natural gas. The long warranty sets it apart.
Amazon $199.99A radiant heater for a drafty room, shop or cabin up to about 700 sq ft on either fuel. Radiant heat suits spaces where warm air escapes.
Amazon $209Prices were last checked November 2, 2026 and are subject to change; the price and availability shown by the retailer at the time of purchase apply.
Each factor is scored 0-100 against the same fixed reference points for every vent-free gas wall heater; a clear win is highlighted. How we rank explains each one.
| Factor weight | Mr. Heater 20K Blue Flame Dual Fuel | Mr. Heater 20K Radiant Dual Fuel |
|---|---|---|
| Overall rating | 4.2/5 | 4.2/5 |
| Value 30% | 64 $10 per 1,000 BTU ($199.99, 20,000 BTU) | 61 $10.45 per 1,000 BTU ($209, 20,000 BTU) |
| Heat output 15% | 50 20,000 BTU/hr | 50 20,000 BTU/hr |
| Controls 20% | 75 thermostat, electronic ignition | 75 thermostat, electronic ignition |
| Fuel 5% | 100 runs on propane or natural gas | 100 runs on propane or natural gas |
| Warranty 30% | 100 5-year warranty | 100 5-year warranty |
| Mr. Heater 20K Blue Flame Dual Fuel | Mr. Heater 20K Radiant Dual Fuel | |
|---|---|---|
| Heat | ||
| Venting | Vent-free | Vent-free |
| Heat type | Blue flame | Infrared |
| Maximum input | 20,000 BTU/hr | 20,000 BTU/hr |
| Heating area claim | 700 sq ft | 700 sq ft |
| Fuel and controls | ||
| Fuel | Dual fuel | Dual fuel |
| Thermostat | Yes | Yes |
| Blower | No | No |
| Ignition | Electronic (battery) | Electronic (battery) |
| Needs an outlet | No | No |
| Oxygen depletion sensor | Yes | Yes |
| Build | ||
| Warranty | 5 years | 5 years |
| Released | 2018-10 | 2018-10 |
