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 rates 4.5 among vent-free gas wall heaters; the Rinnai EnergySaver EX38DTN rates 4.4 among direct vent ones. The Mr. Heater 30K Blue Flame Dual Fuel costs $2,376.83 less ($265.39 vs $2,642.22).
Rinnai EnergySaver EX38DTN
#1 in Direct ventFull review
For a small home, cabin or open plan space that needs one wall unit as the main heat source with modern thermostat control. Owners in outage prone areas should plan a backup.
Amazon $2,642.22$2,642.22
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.
Scores side by side
These two sit in different venting classes (vent-free and direct vent), and each is scored against the reference points for its own class, so a rating says how well each does among its own venting peers. How we rank explains each factor.
| Factor weight | Mr. Heater 30K Blue Flame Dual Fuel | Rinnai EnergySaver EX38DTN |
|---|---|---|
| Overall rating | 4.5/5 | 4.4/5 |
| Value 30% | 73 $8.85 per 1,000 BTU ($265.39, 30,000 BTU) | 61 $68.81 per 1,000 BTU ($2,642.22, 38,400 BTU) |
| Heat output 15% | 100 30,000 BTU/hr | 95 38,400 BTU/hr |
| Controls 20% | 75 thermostat, electronic ignition | 100 thermostat, blower, electronic ignition |
| Fuel 5% | 100 runs on propane or natural gas | 0 natural gas only |
| Warranty 30% | 100 5-year warranty | 100 5-year warranty |
Specifications
| Mr. Heater 30K Blue Flame Dual Fuel | Rinnai EnergySaver EX38DTN | |
|---|---|---|
| Heat | ||
| Venting | Vent-free | Direct vent |
| Heat type | Blue flame | Furnace |
| Maximum input | 30,000 BTU/hr | 38,400 BTU/hr |
| Minimum input | - | 13,200 BTU/hr |
| Heating area claim | 1,000 sq ft | - |
| Efficiency | - | 80% AFUE |
| Fuel and controls | ||
| Fuel | Dual fuel | Natural gas |
| Thermostat | Yes | Yes |
| Blower | No | Yes |
| Ignition | Electronic (battery) | Electronic (120 V) |
| Needs an outlet | No | Yes |
| Oxygen depletion sensor | Yes | - |
| Build | ||
| Weight | - | 86 lb |
| Warranty | 5 years | 5 years |
| Released | 2018-10 | - |