Mr. Heater 30K Blue Flame Dual Fuel
#1 in Vent-freeFull review
The pick for heating a big room on either fuel with a thermostat and a long warranty. Add the blower kit for high ceilings.
Amazon $265.39$265.39
The Mr. Heater 30K Blue Flame Dual Fuel is the better gas wall heater overall, rated 4.5 to 3.4. The Mr. Heater 30K Blue Flame Dual Fuel leads on warranty, controls and fuel. The Comfort Glow KWN523 30K Infrared costs $7.72 less ($257.67 vs $265.39).
Comfort Glow KWN523 30K Infrared
#7 in Vent-freeFull review
A thermostat infrared heater for a large natural gas room, basement or garage. It offers a longer warranty than most budget rivals.
Amazon $257.67$257.67
Prices 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.
Which should you buy?
- Choose the Mr. Heater 30K Blue Flame Dual Fuel for warranty (5-year warranty vs 2-year warranty), controls (thermostat, electronic ignition vs thermostat) and fuel (runs on propane or natural gas vs natural gas only).
Scores side by side
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 30K Blue Flame Dual Fuel | Comfort Glow KWN523 30K Infrared |
|---|---|---|
| Overall rating | 4.5/5 | 3.4/5 |
| Value 30% | 73 $8.85 per 1,000 BTU ($265.39, 30,000 BTU) | 75 $8.59 per 1,000 BTU ($257.67, 30,000 BTU) |
| Heat output 15% | 100 30,000 BTU/hr | 100 30,000 BTU/hr |
| Controls 20% | 75 thermostat, electronic ignition | 50 thermostat |
| Fuel 5% | 100 runs on propane or natural gas | 0 natural gas only |
| Warranty 30% | 100 5-year warranty | 25 2-year warranty |
Specifications
| Mr. Heater 30K Blue Flame Dual Fuel | Comfort Glow KWN523 30K Infrared | |
|---|---|---|
| Heat | ||
| Venting | Vent-free | Vent-free |
| Heat type | Blue flame | Infrared |
| Maximum input | 30,000 BTU/hr | 30,000 BTU/hr |
| Heating area claim | 1,000 sq ft | 1,000 sq ft |
| Fuel and controls | ||
| Fuel | Dual fuel | Natural gas |
| Thermostat | Yes | Yes |
| Blower | No | No |
| Ignition | Electronic (battery) | Push button |
| Needs an outlet | No | No |
| Oxygen depletion sensor | Yes | Yes |
| Build | ||
| Warranty | 5 years | 2 years |
| Released | 2018-10 | 2016-07 |